I ran across this error message a couple days ago working on a laptop.  Every time you would launch this PowerPoint 2003 file it would display.  The guy said that it happened after some Windows Updates ran.

“PowerPoint was unable to display some of the text, images, or objects on slides in the file, “filename”, because they have become corrupted. Affected slides have been replaced by blank slides in the presentation and it not possible to recover the lost information. To ensure that the file can be opened in previous versions of PowerPoint, use the Save As command (File menu) and save the file with either the same or a new name.”

It appears that SP3 for Office 2003 caused this issue.  I uninstalled all of Office and re-installed it.  After that it worked just fine.  I then updated to SP3.  Stopped working again.  I was then able to find a hotfix from MS.  You can get the hotfix here or visit the MS site and request it yourself.