I've heard of problems with Visual Studio "Orcas" - now Visual Studio 2008 Beta 1 and March CTP installed together with VS 2005.

After running the setup of Visual Studio 2008 users had problems opening the .NET Framework configuration MMC snap-in out of administrative tools ("snap-in failed to initialize", ".NET Framework 2.0 Configuration").

clip_image001

When searching for the CLSID in registry I found a hive, where Visual Studio 2008 setup changed something... ;-)

The hive is HKEY_CLASSES_ROOT\CLSID\{A22B5BA1-D8CF-4db6-BC91-CFC1A04E2469}

This is how the normal registry-key should look like:image 

This is what VS 2008 does to it:image

To fix this, delete the hive and import the original VS 2005 version of it (which I appended as .REG file to this post).