A recent security update from Microsoft for PowerPoint 2003 (KB2464588) is causing numerous problems. People who have installed this update have discovered that they are not able to open past presentations that contain background images and items in the slide masters.
When attempting to open a presentation or PowerPoint template in 2003, you receive a message that states that some contents (text, images, or objects) have been corrupted.
Microsoft is aware of this error and is working rapidly to fix it. The most recent news is that this will automatically be fixed through automatic updates in June for people who run Windows Update. Microsoft has released a manual hotfix that is available right now if you do not want to wait until June.
Here is the hotfix link from Microsoft: