Go to Add\Remove Programs, Click Inventor 7 and the Change
Button, then after a few seconds a dialogue pops up and you can choose to
modify, repair, remove.
Failing that try unistalling\reinstalling (sorry if this
sounds like a standard support response but if you are going down this track it
is the next logical thing to try)
--
Best Regards
Richard Rankin
Autodesk
Manufacturing Solutions (Support)