When developing plugins for Visual Studio 2008, your testing is done in what's known as an experimental hive. It's essentially Visual Studio running in a testing environment. This keeps your unfinished plugins from being added to your "real" Visual Studio environment.

Unfortunately, this experimental hive tends to become junky. After going through tutorials, you're bound to have all kinds of unnecessary elements added to the IDE. I spent some time trying to clean this out, and I discovered that the Visual Studio 2008 SDK includes a tool to do this. However, its parameters weren't exactly clear and cause me some grief until I got it right.

Here are the commands that work for me:

"%ProgramFiles%\Microsoft Visual Studio 2008 SDK\VisualStudioIntegration\Tools\Bin\vsregex.exe" GetOrig 9.0 exp RANU
"%ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE\devenv.exe"  /setup /rootsuffix Exp /ranu

The first command clears out your experimental hive then copies your regular registry keys and user profile files over. After I did this, I found that all my templates were missing. The second command fixes that problem.