I have experienced this too. I try to rename roaming folder but it can't be renamed. What should I do? I am using Windows 7 32 bit with inventor 2011 installed. It was working well until yesterday I cant open it.
You will have to login as a different administrator in order to do anything to the profile that is causing you your problems.
Profile degeneration is more of a Microsoft issue than anything else. So hopefully Windows 8 will be better. There are steps one can take to slow the deterioration of one's profile. One of the things I always do is create a dedicated folder for temporary files and then set my Windows environment variables to that folder. Why you ask, because it is easier to find and I clean it out daily. You will be shocked at how much garbage is in there after a days work.
Is there anything I can do to repair this problem without renaming my roaming folder? Because I am afraid that it would damage my other program that used my romaing folder.