Hey I need help!

I got a virus and it ****ed up my pc. Re-formated the hard drive, installed windows xp pro. Now I installed VS.NET and the .NET Framework isnt working right ! Can't open anything made in .NET exept for vs.net.

I've uninstalled it completely (with the .NET Framework & SDK) 2 times ! Still doent work!

The next time I installed the .NET Framework before VS.NET and all my app's worked. Then I installed Vs.NET it wont work anymore!!!!!!!!!!!!!!!!!!!!!

I'm sooo mad!