If you have the SQL Server Management Studio Express CTP or SQL Server 2005, then it is overwriting some registry key settings. The workaround for this is:

1. Under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\Packages\{36839529-3AF3-47fa-8194-F4A3FA9F0ED7}, change the CodeBase value to use the Visual Studio 8.0 location, for e.g. file:///D:\Program Files\Microsoft Visual Studio 8\Common7\IDE\Microsoft.VisualStudio.ToolBoxControlInstaller.dll
2. Under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\Packages\{36839529-3AF3-47fa-8194-F4A3FA9F0ED7}\SatelliteDll, change the Path value to point to the Common7\IDE folder for e.g. D:\Program Files\Microsoft Visual Studio 8\Common7\IDE\
3. Open the Visual Studio Command Prompt and run devenv /setup

This should fix the issue.

Thanks,

Chetan