[John Smith] "I tried applying that hot fix but I just got an error message...
I would report the error to Sony then. I don't know what mscorwks.dll has to do with Vegas. I assume it's some Microsoft program running in the background that causing the problem and not Vegas itself. That's a .Net 2.0 file and Vegas Pro 11 uses .Net 3.5 so it shouldn't even come into the picture. Do you have other software that uses the .Net 2.0 Framework that are also running? Try and close them.
I've read that some malware camouflages itself as mscorwks.dll, particularly when located in the c:\windows or c:\windows\system32 folder. You might want to run an anti-malware/anti-virus scan just to be sure all of your files are legitimate.
~jr
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