By the way If you are running the repair and you can not install net 4.0 that's not good

Then will need to unistall vs 2010 and make sure to delete all your old projects

http://social.msdn.microsoft.com/Forums/en-SG/vssetup/thread/0b0cb100-cec8-447d-8663-c78405d018d7

I have found on 32 bit machines

visual studio has gotten easier to install over the years however 64 bit seems to have  a few problems