If you're working with Visual Studio 2008 (Orcas) Beta builds, of which there are now two, you may have run into problems if you tried to install Beta 2 on the same machine on which you had installed Beta 1. While this is generally not advisable with any beta, I'm told it's working for a great many people. Nonetheless, one behavior you may see is that after installing Beta 2 certain portions of Visual Studio continue to reference the Beta 1 settings under Visual Studio Codename Orcas for instance. One thing you can do that will help with this issue is to run the following from the command line:

devenv.exe /resetsettings

This will clear out the Beta 1 settings for things like the toolbox and other areas. Hope this helps.