I got this exception that doesn't appear anywhere on Google while I was debugging a .NET Core web app. You just have to enable Windows Authentication in the project properties (Debug tab). Duh!

System.InvalidOperationException: The Negotiate Authentication handler cannot be used on a server that directly supports Windows Authentication. Enable Windows Authentication for the server and the Negotiate Authentication handler will defer to it.
   at Microsoft.AspNetCore.Authentication.Negotiate.PostConfigureNegotiateOptions.PostConfigure(String name, NegotiateOptions options)
   at Microsoft.Extensions.Options.OptionsFactory`1.Create(String name)
   at Microsoft.Extensions.Options.OptionsMonitor`1.<>c__DisplayClass11_0.<Get>b__0()
   at System.Lazy`1.ViaFactory(LazyThreadSafetyMode mode)
   at System.Lazy`1.ExecutionAndPublication(LazyHelper executionAndPublication, Boolean useDefaultConstructor)
   at System.Lazy`1.CreateValue()
   at System.Lazy`1.get_Value()
   at Microsoft.Extensions.Options.OptionsCache`1.GetOrAdd(String name, Func`1 createOptions)
   at Microsoft.Extensions.Options.OptionsMonitor`1.Get(String name)
   at Microsoft.AspNetCore.Authentication.AuthenticationHandler`1.InitializeAsync(AuthenticationScheme scheme, HttpContext context)
   at Microsoft.AspNetCore.Authentication.AuthenticationHandlerProvider.GetHandlerAsync(HttpContext context, String authenticationScheme)
   at Microsoft.AspNetCore.Authentication.AuthenticationService.ChallengeAsync(HttpContext context, String scheme, AuthenticationProperties properties)
   at Microsoft.AspNetCore.Authorization.AuthorizationMiddleware.Invoke(HttpContext context)
   at Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware.Invoke(HttpContext context)

This translates to a change in Properties/launchSettings.json like this:

  "iisSettings": {
    "windowsAuthentication": true,
    "anonymousAuthentication": true,

I had this annoying warning that appeared whenever I would build my Wix setup project. I know, Wix sucks, but what can you do? The warning was warning MSB3270: There was a mismatch between the processor architecture of the project being built "MSIL" and the processor architecture of the reference "SomeProject\Some.dll", "AMD64". This mismatch may cause runtime failures. Please consider changing the targeted processor architecture of your project through the Configuration Manager so as to align the processor architectures between your project and references, or take a dependency on references with a processor architecture that matches the targeted processor architecture of your project.

What is worse, the warning would come in the VS Errors window with no warning code, so I couldn't even supress it. And yes, the text above does show a warning code, but it just wouldn't be intrepreted by Visual Studio.

In order to fix it, apparently I had to set ResolveAssemblyWarnOrErrorOnTargetArchitectureMismatch to None, as according to this StackOverflow answer. But where should I add this wonderful property? It didn't work in the .wixproj file, it wouldn't make a difference in the projects mentioned in the warning.

In the end, I decided to customize my build! Final solution:

  • add a file called Directory.Build.props to your solution folder
  • paste in it

Long story short, check out this answer to a StackOverflow question: Package destination of restore of .net-core projects is always global package directory

The scenario is this, you are used to .NET Framework projects for which Visual Studio restored NuGet packages in a packages folder in the solution folder and then you switch to .NET Core. No packages folder! You google it and you find that there is a global folder in your user's profile where NuGet will download all of these projects, that .NET Core uses it by default and also that you might change this behavior used on a property in nuget.config. So here are the issues you have take into account:
  1. There are two ways of configuring NuGet packages for your projects: a packages.config file and PackageReference elements in your .csproj file
  2. The name of the property you need to set is different based on the type of configuration: repositoryPath and globalPackagesFolder, respectively
  3. There are two formats for configuring nuget properties: using the add element inside the config element and using the repositoryPath element inside the settings element
  4. The format that worked for me in VS 2017 was the config element
  5. There are two locations for the nuget.config file: in a .nuget folder inside your solution folder and directly in the solution folder (or any of its parent folders)
  6. The location that is accepted by the latest versions of NuGet is directly in the solution folder
  7. Sometimes you need to restart Visual Studio for the change in nuget.config files to considered
  8. The path you specify is relative to the nuget.config file, no matter where it is

A bit of an overkill, but try this as the beginning of your nuget.config file that sits next to the .sln file in your solution:
<?xml version="1.0" encoding="utf-8"?>
<add key="repositoryPath" value="./packages" />
<add key="globalPackagesFolder" value="./packages" />

This is more a backup for the extensions that I have installed on the two main IDEs I'm using for my job: Visual Studio and Visual Studio Code.

Visual Studio Code

In order to list the extensions installed, use the command code --list-extensions. For me, this results in this output:
code --install-extension aeschli.vscode-css-formatter
code --install-extension Angular.ng-template
code --install-extension christian-kohler.npm-intellisense
code --install-extension cmstead.jsrefactor
code --install-extension cssho.vscode-svgviewer
code --install-extension danwahlin.angular2-snippets
code --install-extension dbaeumer.jshint
code --install-extension dbaeumer.vscode-eslint
code --install-extension donjayamanne.jquerysnippets
code --install-extension donjayamanne.jupyter
code --install-extension DotJoshJohnson.xml
code --install-extension ecmel.vscode-html-css
code --install-extension eg2.vscode-npm-script
code --install-extension esbenp.prettier-vscode
code --install-extension fabianlauer.vs-code-xml-format
code --install-extension fknop.vscode-npm
code --install-extension HookyQR.beautify
code --install-extension humao.rest-client
code --install-extension joelday.docthis
code --install-extension k--kato.docomment
code --install-extension michelemelluso.code-beautifier
code --install-extension minhthai.vscode-todo-parser
code --install-extension mohsen1.prettify-json
code --install-extension mrmlnc.vscode-scss
code --install-extension ms-mssql.mssql
code --install-extension ms-vscode.csharp
code --install-extension ms-vscode.typescript-javascript-grammar
code --install-extension ms-vscode.vscode-typescript-tslint-plugin
code --install-extension msjsdiag.debugger-for-chrome
code --install-extension naumovs.color-highlight
code --install-extension pmneo.tsimporter
code --install-extension rbbit.typescript-hero
code --install-extension robinbentley.sass-indented
code --install-extension wayou.vscode-todo-highlight
In order to install them, use code --install-extension [extension name] for each line.

Visual Studio

For Visual Studio, funny enough, in order to export and import your extensions you need to use an extension: Extension Manager 2017, which on my system exports a file in .vsext format:
"id": "5f191824-b8a6-47c0-9f96-f607dfd3c09b",
"name": "My Visual Studio extensions",
"description": "A collection of my Visual Studio extensions",
"version": "1.0",
"extensions": [
"name": ".NET Portability Analyzer",
"vsixId": "55d15546-28ca-40dc-af23-dfa503e9c5fe"
"name": "Advanced Installer for Visual Studio 2017",
"vsixId": "Caphyon.AdvancedInstaller.23debb5a-cff4-4b91-88bf-6280f72a7ebb"
"name": "Azure Data Lake and Stream Analytics Tools",
"vsixId": "1e906ff5-9da8-4091-a299-5c253c55fdc9"
"name": "Azure Functions and Web Jobs Tools",
"vsixId": "Microsoft.VisualStudio.Web.AzureFunctions"
"name": "BuildVision",
"vsixId": "837c3c3b-8382-4839-9c9a-807b758a929f"
"name": "Clean Code .NET",
"vsixId": "CleanCode.NET.9ecfa9bb-0775-48d0-9898-4dbbbd529fe3"
"name": "Cloud Explorer for VS 2017",
"vsixId": "Microsoft.VisualStudio.CloudExplorer"
"name": "Code Cracker for C#",
"vsixId": "CodeCracker.Vsix..5b99e64c-1418-4a06-990c-fd4cf01f4f63"
"name": "Code Graph",
"vsixId": "CodeAtlasVSIX.Company.df5456fb-08ea-4256-b5ff-ecdb3a512ad3"
"name": "CodeMaid",
"vsixId": "4c82e17d-927e-42d2-8460-b473ac7df316"
"name": "CommentCop",
"vsixId": "CommentCop..0521EE68-1A5D-4C78-9970-B6A46B03FA6D"
"name": "EntityFramework Reverse POCO Generator",
"vsixId": "EntityFramework_Reverse_POCO_Generator..d542a934-8bd6-4136-b490-5f0049d62033"
"name": "Extension Manager 2017",
"vsixId": "e83d71b8-8bfc-4e06-b145-b0388910c016"
"name": "Fix Mixed Tabs",
"vsixId": "FixMixedTabs.9f1d3050-b986-4b10-ae36-97c6efc5e968"
"name": "Fix Namespace",
"vsixId": "f073da8c-bb52-41f8-b95a-a6346b1a0b52"
"name": "MetricsAnalyzer",
"vsixId": "MetricsAnalyzer..8026235d-7afc-401b-8f45-ba8624a07ef5"
"name": "Microsoft Code Analysis 2017",
"vsixId": "4db2d63d-3320-4fbd-bf80-07f8d1500bd3"
"name": "Moq.Analyzers",
"vsixId": "Moq.Analyzers..c3c7e3f8-2407-428d-beef-c4557253517b"
"name": "Object Exporter",
"vsixId": "07fb5b16-f4be-4488-9a19-b4f36d2c05a6"
"name": "Output enhancer",
"vsixId": "VSOutputEnhancer.Nikolay Balakin.a06be4c3-f97e-425c-8a0d-bdef08ac2abb"
"name": "Power Commands for Visual Studio",
"vsixId": "PowerCommands.3ecdd89b-f985-483d-8c94-be37de4dc083"
"name": "Ref12",
"vsixId": "SLaks-Ref12-086C4CE4-7061-4B1F-BC77-B64E4ED71B8E"
"name": "Reference Conflicts Analyser",
"vsixId": "ff477521-e67b-4ca3-931f-3edf36125d28"
"name": "Regular Expression Tester Extension",
"vsixId": "a65d58d2-ead8-4eea-a47d-fa60865a6043"
"name": "ResolveUR - Resolve Unused References",
"vsixId": "637ba02c-3388-4e54-9051-3eea7c51b054"
"name": "Roslyn Security Guard",
"vsixId": "RoslynSecurityGuard..45fa56c2-16f1-4395-8c10-a5a460084018"
"name": "Roslynator 2017",
"vsixId": "9289a8ab-1bb6-496b-9992-9f7ea27f66a8"
"name": "Security Code Scan (for VS2017 and newer)",
"vsixId": "955196A7-ACBF-4F6B-820B-51B8507CE853"
"name": "Solution Error Visualizer",
"vsixId": "SolutionErrorVisualizer.a392f96b-6b33-4b53-b4bb-3376a05f986c"
"name": "SonarLint for Visual Studio 2017",
"vsixId": "SonarLint.36871a7b-4853-481f-bb52-1835a874e81b"
"name": "SQL Search",
"vsixId": "Redgate.SQLSearch.VSExtension.9BD7AEDA-C291-4702-8191-4189B099F3A9"
"name": "Target Framework Migrator",
"vsixId": "TargetFrameworkMigrator..4f7666b9-e62c-46a1-af25-21ab8742ef00"
"name": "Trailing Whitespace Visualizer",
"vsixId": "4c1a78e6-e7b8-4aa9-8812-4836e051ff6d"
"name": "Unit Test Boilerplate Generator",
"vsixId": "UnitTestBoilerplate.RandomEngy.ca0bb824-eb5a-41a8-ab39-3b81f03ba3fe"
"name": "Visual Studio IntelliCode",
"vsixId": "IntelliCode.VSIX.598224b2-b987-401b-8509-f568d0c0b946"
"name": "Visual Studio Spell Checker (VS2017 and Later)",
"vsixId": "43EA967E-0DE2-4136-8E52-C6DCFB5C2748"
"name": "Wix Toolset Visual Studio 2017 Extension",
"vsixId": "WixToolset.VisualStudioExtension.Dev15"

Sometimes you get an annoying error after updating your .NET Framework or some of the packages or libraries in your project: "Some NuGet packages were installed using a target framework different from the current target framework and may need to be reinstalled. Visit http://docs.nuget.org/docs/workflows/reinstalling-packages for more information. Packages affected: <name-of-nuget-package>".

The problem stems from the fact that NuGet packages have variants for different .NET flavors and in your project they are "hinted" at by the <HintPath> child element in the <Reference> elements in your .csproj file. Somehow, the hint still points to a different variant than the one you need and that's why you get this error. The explanation in length can be found in this great post: Why, when and how to reinstall NuGet packages after upgrading a project, but just in case his blog disappears (as so many great ones did in the past), here is the gist of the solution:

In Visual Studio go to Tools → NuGet Package Manager → Package Manager Console and type:
Update-Package <name-of-nuget-package> -Reinstall -ProjectName <name-of-project>

To add some value to Derriey's post, you can solve all the similar issues in your solution by copying the entire list of errors from all projects by going to the Output pane, selecting them all and right clicking Copy, then run search and replace in your favorite editor with this regular expression:
^.*?Visit http://docs.nuget.org/docs/workflows/reinstalling-packages for more information.  Packages affected: ((?:[^,\s]+(?:, )?)+)\t([^\t]+)\t\t\d+\t\t$
and replacement pattern
Update-Package $1 -Reinstall -ProjectName $2

Then make sure there is only one project on each line, copy paste the result into the Package Manager Console window and the entire solution will get fixed.

Example: Error Some NuGet packages were installed using a target framework different from the current target framework and may need to be reinstalled. Visit http://docs.nuget.org/docs/workflows/reinstalling-packages for more information. Packages affected: Microsoft.Extensions.Configuration, Serilog MyProject.Common 0

Turns into: Update-Package Microsoft.Extensions.Configuration, Serilog -Reinstall -ProjectName MyProject.Common Since Update-Package only supports one package and regex replace doesn't have a syntax for multiple captures in the same group, you will have to manually turn this into:
Update-Package Microsoft.Extensions.Configuration -Reinstall -ProjectName MyProject.Common
Update-Package Serilog -Reinstall -ProjectName MyProject.Common

Copy paste the result and the two projects will be reinstalled on the affected projects in your solution.

I spent hours trying to manually fix the assembly redirects in a web.config, only to give up and use the default Add-BindingRedirect in the NuGet package manager. And it worked! I have no idea if this won't break something else, but I got it from Rick Strahl's blog and it worked for me. More in his article. Thanks, Rick!

One thing to remember is that you first have to delete the dependentAssembly elements from the .config file in order for the command to work.

Update: there is an issue related to NuGet packages. I was recommending to run MsBuild with the command line option /t:Restore;Rebuild which should restore packages and rebuild the solution. However, as detailed here, the MSBuild Restore option only restores packages defined in the project PackageReference elements, not the ones in packages.config. In order to restore those, you still need to manually run nuget restore. Where do you get nuget.exe from? Obviously not from the Visual Studio Build Tools... but from the NuGet Gallery.

Now, for the original post.

So I had this medium size Visual Studio solution, in .NET Framework 4.6.1, containing a bunch of projects, including a Wix setup and a web API and I wanted to build it on a machine that did not have Visual Studio, for Continuous Deployment reasons. Since Visual Studio uses MSBuild to compile, I thought it would be a five minute job. Boy, was I wrong!

First of all, the command to build a solution is clear:
MSBuild You.sln
and since it was a .NET 4.0 project, it made sense to use the MSBuild.exe from C:\Windows\Microsoft.NET\Framework64\v4.0.30319. Well, enter the first error: CS1617: Invalid option 'latest' for /langversion; must be ISO-1, ISO-2, 3, 4, 5 or Default. This is caused by the project using C# version 7 which is NOT supported by the MSBuild version in the .NET Framework, you need MSBuild version 15, which comes with Visual Studio. I didn't want to install Visual Studio.

The solution is to install Visual Studio Build Tools, preferably using the Visual Studio Installer. Now, the correct MSBuild version is found at C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\15.0\Bin\MSBuild.exe. Note that it is in located in a Visual Studio folder, not the MSBuild folder, which is also there.

An issue that occurred here was that previously warning messages saying the framework is 4.6.1 and the installed framework is 4.7.2 now became errors. The solution is to install the .NET Framework SDK 4.6.1 or to upgrade all your projects to 4.7.2. Warning: you need the Developer Pack, not just the Runtime.

Second error: error MSB4036: The "GetReferenceNearestTargetFrameworkTask" task was not found.. The problem? The NuGet package manager and/or the NuGet targets and build tasks are not installed. In order to install them, run Visual Studio Installer and look under the Individual Components tab, in the Code Tools section. See this Stack Overflow question for more details.

Next problem: The type 'IDisposable' is defined in an assembly that is not referenced. You must add a reference to assembly 'netstandard'. This is a weird one, since the compilation in Visual Studio had no issues whatsoever. This is related to the framework version, though, as .NET 4.6 uses netstandard 1.0 and 4.7 uses 2.0. The solution is to add a <Reference Include="netstandard" /> tag in your .csproj (tip: Search and replace <Reference Include="System" /> with <Reference Include="System" /><Reference Include="netstandard" /> in all your .csproj files)

Another problem similar to the one above is Predefined type 'System.ValueTuple´2´ is not defined or imported and that is because ValueTuple is not in .NET Framework 4.6.2 or earlier and you need to install the System.ValueTuple package in your project (using the NuGet package manager, more details here)

For both problems above as well as for the issue with the framework conflict further up a possible solution is to upgrade all projects to .NET 4.7+ or whatever is latest.

Next, targets errors: error MSB4226: The imported project "Microsoft.WebApplication.targets was not found. and error MSB4057: The target "_WPPCopyWebApplication" does not exist in the project. This is because even if Visual Studio Build Tools is installed, the targets for it are not. The solution is to copy the folders Web and WebApplications from C:\Program Files (x86)\Microsoft Visual Studio\2017\Professional\MSBuild\Microsoft\VisualStudio\v15.0 to "\\BuildMachine\C$\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\Microsoft\VisualStudio\v15.0". You may need to copy the NuGet targetss as well, I don't remember if that is what I did or the NuGet package manager installation solved it.

Last but not least, Wix errors. Obviously, for the Setup project to compile you need to install the Wix Toolset. However, you may still run into this error: error MSB3073: The command "heat dir ..blah blah blah" exited with code 9009. If you were trying to executing the build from a command prompt and you installed Wix while it was open, you need to open another one in order to refresh the changes the installer did to your environment PATH variable.

Finally, in order to compile for a specific platform and configuration, use the flags: /property:Configuration=Release /property:Platform=x64.

Then just run the line:
nuget restore
"c:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\MSBuild\15.0\Bin\MSBuild.exe" /t:Restore;Rebuild Your.sln /property:Configuration=Release /property:Platform=x64

Hope it helps.


Visual Studio has a very interesting feature called Rule Sets. You basically create a file where you declare which warnings from analyzers will be ignored, displayed as info, warning or error. With the built in code analysis, but also with the help of a plethora of extensions and NuGet packages, this can be a very powerful tool. I am using VS2017 Professional for this post.

Create a rule set

Let's start with creating a new project (a .NET Framework console app) called Rulesets, which will create the standard Program.cs file and a solution for the project. Next, right click the solution in Solution Explorer and go to Add → New Item, go to the General category and select Code Analysis Rule Set. Name it whatever you want to name it, I will call it default.ruleset, then save it.

At this point you should be in a rule set editor, showing you a list of rules grouped by code analyzer id. Press F4 or go to the little wrench icon so that the Properties window is open, then give your ruleset a name (Default Rule Set) and save the file (ctrl-S).

You can create as many of these files and they will be saved in the Solution Items or as a file in a project (I recommend the former) and associate them to any number of projects. Let's assign the new rule set to our project: Go to the solution properties, select Common Properties → Code Analysis Settings, then select as many projects as you want in the list in the right. Then click on the little dropdown arrow an you should be prompted with a list of possible rules, including Default Rule Set. Select it.

Obviously, you can just choose a Microsoft included rule set instead, but those do not take into account your own extensions/packages.

Note: in order to start an incremental process, let's say starting with the minimum recommended settings from Microsoft and then adding stuff to it, use the Include element in a .ruleset file. The files coming by default with Visual Studio can be found at %ProgramFiles(x86)%/Microsoft Visual Studio/2017/Professional/Team Tools/Static Analysis Tools/Rule Sets. Example:
<Include Path="minimumrecommendedrules.ruleset" Action="Default" />

From the Visual Studio GUI you can click on the folder icon in the rule set editor top bar to include other sets and the wrench icon to open the settings.

This helps a lot with having small variations between your projects. For example a tests project might have different settings. Or the data access layer project might have auto generated files that don't respect your coding standards. You can just create a new ruleset that includes the default, then disables some of the rules, like mandatory class documentation.

Note that the rule set editor is not perfect. It will only show the rules as defined in the current file, ignoring the included sets. That is why if the default for a rule is None and you set it to Warning in your base set which you then include in another set where you set it back to None, it will not be saved correctly. Some manual checks are required to ensure correctness.

A list of analyzers

Now, I've noticed a list of possible extensions for Visual Studio that use this system. Here is a list of the ones I thought were good enough, free and useful.
Visual Studio extensions:
  • Microsoft Code Analysis 2017 - Live code analysis rules and code fixes addressing API design, performance, security, and best practices for C# and Visual Basic.
  • Security Code Scan - Detects various security vulnerability patterns: SQL Injection, Cross-Site Scripting (XSS), Cross-Site Request Forgery (CSRF), XML eXternal Entity Injection (XXE), etc.
  • MetricsAnalyzer - analyzer extension to check if you code follow metrics rules
  • Moq.Analyzers - Visual Studio extension that helps to write unit tests using Moq mocking library by highlighting typical errors and suggesting quick fixes
  • Code Cracker for C# - analyzer library for C# that uses Roslyn to produce refactorings, code analysis, and other niceties
  • Visual Studio Intellicode - this is interesting in the sense that it uses AI to improve your code and intellisense
  • Roslynator 2017 - A collection of 500+ analyzers, refactorings and fixes for C#, powered by Roslyn.
  • SonarLint for Visual Studio 2017 - Roslyn based static code analysis: Find and instantly fix nasty bugs and code smells in C#, VB.Net, C, C++ and JS.
  • clean-code-net - Set of C# Roslyn analyzers to improve code correctness
  • CommentCop - Analyzes (mostly) xml comments and provides code fixes. Uses Roslyn C# code analyser.

NuGet packages:
  • StyleCop.Analyzers - there is also a StyleCop extension, but weirdly it does not use the Rule Set system and you just run it manually and gives you warnings that you can control only through the extension configuration
  • Public API Analyzer - An analyzer for packages with public APIs.
  • UnityEngineAnalyzer - Roslyn Analyzer for Unity3D
  • AsyncAwaitAnalyzer - A set of Roslyn Diagnostic Analyzers and Code Fixes for Async/Await Programming in C#.
  • ef-perf-analyzer - EntityFramework Performance Analyzer
  • Asyncify-CSharp - an analyzer and codefix that allows you to quickly update your code to use the Task Asynchronous Programming model.

The packages above are NuGets you install in your project. Just check out the list from NuGet: NuGet packages containing Analyzer. Many extensions also have a NuGet counterpart. It's your choice if you want to not bloat your Visual Studio and choose to install analyzers on a per project basis. There is one advantage more in using project packages: the analysis will pop up at build time and you can thus enforce not being able to compile without following the rules in the set.

Curating your rule sets

So you've learned how to choose a rule set for your projects, how to create your own, but what do you use them for? My suggestion is to work on a complete rule set (or sets) for your entire company and then you can just enforce a coding style without having to manually code review everything.

If you are like me, then you probably installed everything in that list above and then tried it on your project... and you got tens of thousands of warnings and errors. How do you curate a rule set without having to go through every single message? I see several ways of doing this.

The perfect project

Some people/companies have a flagship technical project that they are very proud of. It uses all the latest technologies, it is perfectly written, thoroughly code reviewed by all the members of the team. It can do no wrong. If you have such a project, just enable all possible rules, then disable all that make suggestions for change. In the end you will have a rule set enforcing your coding style, for better or worse.

Start from scratch

The other solution is to start with a new project, then review every message until you get none. Then start coding. An iterative process, for sure, one you will never finish, but it will be good enough after a while and it will also engage your team in technical discussions on how to improve their code, which can't possibly hurt.

Add analyzers one by one

Start with a rule set where all rules are disabled, then start reviewing them one by one, as you either chose to disable them or refactor your code. This solution may be the worse, because it gives excuses to just stop the process midway, but it might be the only one available. Anyway, try to install extensions and packages one by one, too.

Start from the coding standards

Perhaps you have a document describing the coding standards in your team. You might start from it, then look for the rules that enforce it. I think that this will only make you see how woefully inadequate your coding standards are, but it might work.

Other notes

I've had the situation where I created derived rulesets from the default one (using Include) and somehow they ended up with an absolute path for the default ruleset file. It might be an issue with how the editor saves the file.

By default, rules in the ruleset editor are grouped by analyzer ID, but multiple analyzers might manage the same rules, so always manage rules individually, else you will see that enabling or disabling an entire group will change other groups as well and you won't know where you started from.

The ruleset editor is not perfect. One very annoying issue is with ruleset inheritance (doesn't load the parent rules). One example is that you want to have a general ruleset that does NOT include an analyzer (let's say the XUnit one) and then you want something inheriting the base ruleset to DO include the XUnit analyzer. While you can do it by hand, the ruleset editor will not allow you to make these changes, as the original ruleset will have every XUnit rule disabled, but the editor for the unit test one will not know this. There are two solutions for this:
  1. Have a very inclusive basic rule set, then remove rules from the others. This is not perfect, as there could be circular needs (one set has one rule and not the other, while the other has them the other way around)
  2. Have a lot of basic rule sets, split on topic. Then manage every rule set that you need as just includes. This works in every situation, but requires you edit the used rulesets by hand. In the case above you could have a special DoNotUseXunitAnalyzers.ruleset, for example.
  3. A third solution that I do not recommend is to never include anything, instead just copy paste the content of the basic ruleset in every inheriting one. While this works and allows the editor and whatever engine behind to work well, it would be a nightmare to maintain.


I've discussed how to define and control static code analysis in your Visual Studio projects. If nothing of what is available is up to your standards, Roslyn now allows making your own code analyzers in a very simple way. Using code analyzers (and refactorings) can improve productivity, engage the team in technical analysis of standards, enforce some coding standards and help you find hard to detect errors in your code.

Hope it helps.

I was under the impression that .NET Framework can only reference .NET Framework assemblies and .NET Core can only reference .NET Core assemblies. After all, that's why .NET Standard appeared, so you can create assemblies that can be referenced from everywhere. However, one can actually reference .NET Framework assemblies from .NET Core (and not the other way around). Moreover, they work! How does that happen?

I chose a particular functionality that works only in Framework: AppDomain.CreateDomain. I've added it to a .NET 4.6 assembly, then referenced the assembly in a .NET Core program. And it compiled!! Does that mean that I can run whatever I want in .NET Core now?

The answer is no. When running the program, I get a PlatformNotSupportedException, meaning that the IL code is executed by .NET Core, but in its own context. It is basically a .NET Standard cheat. Personally, I don't like this, but I guess it's a measure to support adoption of the Core concept.

What goes on behind the scenes is that .NET Core implements .NET Standard, which can reference .NET Framework assemblies. For this to work you need .NET Core 2.0 and Visual Studio 2017 15.3 or higher.

I did something and suddenly my API was not run in IIS Express anymore, but in Kestrel. I reviewed code changes, configuration changes, all to now avail. I don't want Kestrel, I want IIS Express!!! Why did Visual Studio suddenly decided to switch the development server?

Solution: it is your Visual Studio. The button you use to start debugging has a little dropdown that allows you to choose which server to use. I had probably pressed the wrong one at some point.

I had this memory problem that I could not understand. OK, the design of the application was not the best in the world, but why would it always give me a damn OutOfMemoryException when I have a super duper computer with a lot of memory and I have solved issues like heap memory allocation? And the reason is that IISExpress, the default Windows7 ASP.Net web server is running in 32bit mode, meaning it has a maximum of 4GB of memory no matter what you do. Well, you can make IISExpress run in 64bit mode by simply switching it on in the Windows registry. I don't want to copy the content of the article from someone else, so here is a link towards how to do it: Debugging VS2013 Websites Using 64-bit IIS Express.

Just in case you want the ultra fast version, copy this into a file with the .reg extension and execute it:
Windows Registry Editor Version 5.00



This has happened to a colleague of mine: when trying to open a solution file with VS 2010 the program would start, it would successfully load the solution, open the few files that were open when last closed, then suddenly restart. No fancy dialog prompting for action, no message of any kind, just a total silent fail. He tried using the /log filename option of Visual Studio to gather more information, it did not help. He tried using the /SafeMode switch to load only the essential bits of Visual Studio, to no avail. The only useful information was in the Windows Application log (run eventvwr.exe in the command line) which pointed to the module cslangsvc.dll failing.

The Windows Application log entry for the crash:
Faulting application name: devenv.exe, version: 10.0.40219.1, time stamp: 0x4d5f2a73
Faulting module name: cslangsvc.dll, version: 10.0.40219.1, time stamp: 0x4d5f3b95
Exception code: 0xc0000005
Fault offset: 0x00249be1
Faulting process id: 0x1af8
Faulting application start time: 0x01ce3c253d1db9e5
Faulting application path: C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\devenv.exe
Faulting module path: C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC#\VCSPackages\cslangsvc.dll
Report Id: f3522e88-a818-11e2-a285-14109fd5a416

The bit of the Visual Studio log that is relevant:
<time>2013/04/18 11:17:35.042</time>
<description>Unexpected system error mode before loading package [Visual Studio XML Editor Package]</description>

At this point, we thought that it was a problem caused by Visual Studio trying to parse the open files, probably related to Intellisense, which means we need to make the solution open ignoring the files open when using it last time. That means deleting the file with the .suo extension associated to the solution.

This is a common issue, as the first Google search item when looking for cslangsvc.dll is this: Visual Studio 2010 Crashing on Solution Load. The thing is the guy does claim he deleted his .suo file and that the problem was still reproducing. There are also some Microsoft Connect items logged (Vs2010 crashes on cslangsvc.dll) that have no resolution.

Well, deleting the .suo file associated with the solution worked. This, of course, removes more than the last opened files, like the source control associations of the solution, various custom options for said solution, etc, but it shouldn't be a problem.

There is a bit of information in the Visual Studio log which points to the XML Editor Package. This means it could be caused by XML files or aspx/ascx files. However, it might not. We did not pursue the issue any further. Hope it helps other people looking for a resolution.

I've had a horrible week. It all started with a good Scrum sprint (or so I thought) followed by a period of quiet in which I could concentrate on my own ideas. And one of my ideas was to optimize the structure of the solution we work on, containing 48 projects, in order to save space and compilation time. In my eyes, I was a hero, considering that for a company with tens to hundreds of devs, even a one second increase in speed would be important. So, I set up doing that.

Of course, the sprint was not as good as I had imagined. A single stored procedure led to not less than four bugs in production, with me being to blame for them all. People lost more time working on reproducing the bugs, deploying the fix, code reviewing, etc. At long last I thought I was done with it and I could show everyone how great the solution looked now (on my computer) and atone for my sins.

So from a solution that spanned from 700Mb clean and 4Gb after compilation, I managed to get it to a maximum of 1.4Gb. In fact, it was so small I could put it all in a Ram disk, leading to enormous speeds. In comparison, a normal drive goes to about 30MB per second, an SSD drive (without encryption) goes to about 250MB/s, while my RamDisk was running at a whooping 3.6GB/s. That sped up the compilation and parsing of files. Moreover, I had discovered that MsBuild has this /m parameter that makes it use more processors. A compilation would go to about 40 seconds, down from two minutes and a half. Great! Alas, it was not to be so easy.

First of all, the steps I was considering were simple:
  • Take all projects and make them have a single output folder. That would decrease the size of the solution since there would be no copies of the .dll files, Then the sheer speed of the compilation would have to increase, since there would be less copying and less compilation.
  • More importantly, I was considering making a symlink to a RAM drive and using it instead of the destination folder.
  • Another step I was considering was making all references to the dll files in the output folder, not to the projects, allowing for projects to be opened independently.

At first I was amazed the solution decreased in size so much and I just placed the entirety of it into a RAM drive. This fixed some of the issues with Visual Studio, because when I was selecting a file through a symlink to add as a reference, it would resolve to the target folder instead of the name of the symlink. And it was't easy either. Imagine removing all project references and replacing them with dll references for 48 projects. It took forever.

Finally I had the glorious compilation. Speed, power, size, no warnings either (since I also worked on that) and a few bug fixes thrown in there for good measure. I was a god! Then the problems appeared.

Problem 1: I had finished the previous sprint with a buggy stored procedure committed to production. Clients were losing money and complaining. That put a serious dent in my pride, especially since there were multiple problems coming from both less attention to how I wrote the code to downright lack of knowledge of the flow of the application. For the last part I am not really the only one to blame, but it was my responsibility.

Problem 2: The application was throwing some errors about the target framework of a dll. It was enough to make me understand a major flaw in my design: there were .Net 3.5 and .Net 4.0 assemblies in the solution and placing them all in the same output folder would break some build scripts. Even worse, the 8 web projects in the solution needed to have their output in the bin folder, so that IIS would find them. Fixed it only to see the size of the solution rise back to 3Gb.

Problem 3: Visual Studio would not be so smart as to understand that if a project is loaded, going to the declaration of a member in the compiled assembly means I want to see the actual source, not the IL code. Well, sometime it worked, but sometimes it didn't. As a result I restored the project references instead of the assembly references.

Problem 4: the MsBuild /m flag would do wonders on my machine, but it would not do much on the build server. Nor would it do its magic on slower, less multiprocessor computers than my own.

Problem 5: Facing a flood of problems coming from me, my colleagues lost faith and decided to not even try the modifications that removed the compilation warnings from the solution.

Conclusion: The build went marginally faster, but not enough to justify a whole week of work on it. The size decreased by 25%, making it feasible to put it all in a RAM Drive, so that was great, to the detriment of working memory. I still have to see if that is a good or a bad thing. The multiprocessor hacks didn't do much, the warnings are still there and even some of my bug fixes were problematic because someone else also worked on them and didn't tell anyone. All in a week's work.

Things I have learned from all this: Baby steps. When I feel enthusiasm, I must take it as a sign of trouble. I must be dispassionate as an ice cube and think things through. If I am working on a branch, integrate the trunk into it every day, so as to not make it harder to do at the end. When doing something, do it from start to finish, no matter what horrors I see while doing it. Move away from Sodom and not look back at it. Someone else will fix that, maybe, you just do your task well. When finishing something, commit it into the source control so it can easily be reverted through a single atomic operation.

It is difficult to me to adjust to something that involves this amount of planning and focus. I feel as if the chaotic development years of my youth were somewhat better, even if at the time I felt that it was stupid and focus and planning was needed. As a good Romanian, I am neurotic enough to see the worst side of everything, master at complaining about it, but incapable of actually doing something. Yeah... this was a bad week.

People who know me also know about the Law of Siderite: never use any Microsoft product until it has reached a second service pack or release. That has been true for me, like a skewed Moore law, since Windows 95 OSR2 (also known as Windows 96). But I had to break my own legal advice and try to install Visual Studio 2010 Service Pack 1.

There are several reasons for this, one of them being that VS2010 had a few relatively important bugs and I am using the tool at work every day and at home when I get the time. So not only did I not wait for a Service Pack 2, I've gone and installed the beta version! And guess what? It installed without any problems and fixed most of the bugs that annoyed me, if not all. Yay, for Microsoft! But then I had to install ASP.Net MVC, which needed as a prerequisite VS2010 SP1 and so I went and installed the Release Candidate. That is, the version that should be like the beta, only better. This is the story of that fateful decision:
  • Step 1: Start ASP.Net MVC3 installer. Result: Fail!
  • Step 2: Start Visual Studio 2010 Service Pack 1 installer, the small 500kb version. Result: fail.
  • Step 3: Download the .iso version and run. Result: fail.
  • Step 4: Reinstall Visual Studio 2010 Ultimate
    a) Uninstall Visual Studio 2010. Result: fail.
    b) Use Microsoft Installer Cleanup Utility on Visual Studio. Install VS2010 (without VB or VC++). Result: Success!
  • Step 5: Install VS2010 SP1
    a) .iso version. Result: fail!
    b) Web Platform Installer version (new fancy Microsoft tech). Result: fail!
  • Step 6: Install Web Developer Express (free) + VS2010 SP1 from Web Platform Installer. Result: SP1 core fail! SP1 Asp.net success!?!

Bottom line: Now ASP.Net MVC seems to be working, with Razor syntax highlighting and intellisense, but the SP1 core is not installed. Visual Studio help window shows me that I have the Rel(ease) version, not SP1. I don't know what will blow up when I try it. Luckily, all this happened at home, not at work, therefore I haven't broken my main working tool.

My conclusion is that somehow you need to install the (useless, if you have Visual Studio) Visual Web Developer Express in order for the ASP.Net SP1 to work. This allows for different web engines, like Razor. SP1 doesn't work though. If you have the beta installed, try to use the Web Platform Installer to install Web Developer Express as well as the Visual Studio SP1. If it fails, look at the last section and see what got installed. Maybe you get the best of both worlds. I will be trying another Visual Studio version, but as the whole process takes ages, be warned.

Let me say that again, so it's perfectly clear: the install process of Visual Studio 2010 Service Pack 1 plus Visual Web Developer Express via the Web Platform Installer tool took me 12 hours! I did not have to press anything, it wasn't a case of trial and error, I just ran it, it said "installing 2 out of 12" for 12 hours in a row, then it partially failed. And the Web Platform Installer seems the best solution so far!

Today a power outage screwed something in my Visual Studio installation. For the life of me I couldn't figure out what went wrong and I also didn't have the time to properly investigate. The issue appeared when I restarted the computer, ran Visual Studio 2010, loaded a project (any project) and tried to compile. Invariably, an error would prevent me from building the project:Error 22 A problem occurred while trying to set the "Sources" parameter for the IDE's in-process compiler. Error creating instance of managed object 'Microsoft.VisualStudio.CSharp.Services.Language.Features.EditAndContinue.EncState' (Error code is 0x80131604). Application.

I have tried disabling Edit and Continue, I've tried to disable the Exception Assistant and also I've re-registered the dlls in the Visual Studio 10.0/Common7/IDE folder, all to no avail. Even worse, it seemed as I am the only person on Google (yay!) that got this error so I couldn't find a quick no effort solution (boo!). The error code 0x80131604 stands for HRESULT COR_E_TARGETINVOCATION, or a TargetInvocationException, which is thrown by methods invoked through reflection. So that is that.

The solution was to reinstall Visual Studio. It took half a day, but it fixed it. If you have met the same issue and you found a quicker way, please leave a comment.