Ya lo resolví, les pego esta solución que encontré para el que tenga el mismo problema:
Cita: Perhaps i have found the solution. Please try this.
I have German VISTA x64 and VS2008 Professional in german)
1. run Visual Studio 2008 prompt ("Visual Studio 2008-Eingabeaufforderung"
2. run "devenv /resetaddin" => close VS2008
3. run "devenv /resetskippkgs" => close VS2008
4. run "devenv /resetsettings" => close VS2008
5. close prompt
6. run VS2008 normal (under VISTA with "RUN AS Administrator"
In my configuration VS2008 works fine.
Un abrazo!