Your Silverlight developer components are out of date

For a few weeks I have been having problems running Silverlight on my machine, especially since I had SL3 installed and also Expression Blend, version 3. I didn't mind much, because I don't need Silverlight most of the time. But since sometimes I do, here is the solution for the "Your Silverlight developer components are out of date" error when trying to install Silverlight.

Go to http://go.microsoft.com/?linkid=9394666 and install the Silverlight tools. Yes, they are version 2. No, I don't know why Silverlight 3 would have problems because of version 2 Silverlight tools. However, installing the tools solved my problem.