Originally Posted by SlySoft

The "File corrupted - please reinstall AnyDVD & run a virus check" message is only displayed, if the AnyDVD executable has been modified. It is a simple integrity check. Reinstalling AnyDVD will always repair the problem. This message will not be displayed for any other reason (wrong registration key, etc.)
The question is - why was the AnyDVD executable changed. One reason could be a virus infection (hence the message "run a virus check"). Another could be a hardware problem (but I doubt that the computer would run stable long enough to even boot Windows).
If you modify AnyDVD intentionally - either by using a hex editor, or by using one of the various "cracks" - you will see this message sooner or later.
If you see this message, I would say in 99.99% of the cases you have used a patch to bypass the registration check.