[imjustmatthew]

It could have something to do with C-Dilla, the licensing system used with Autodesk products. We had a heck of a time trying to get 3dsmax 5 to run on a win 2k computer without full admin privleges. We didn't try inventor until after we bought our own computer so we could have admin rights, then it worked fine. We also haven't had running other copies (that we won't discuss) on WinXP machines, but none of us use Partition Magic.

You could try uninstalling C-Dilla to see if it is causing the problem. (Do this from Control Panel>Add/Remove Programs) However, BE WARNED THAT YOU WILL HAVE TO REINSTALL C-DILLA AND REAUTHORIZE INVENTOR AFTERWARDS FOR INVENTOR OR 3DSMAX TO WORK.