1. Find and delete your *.PCB file. This is the PPT toolbar. PPT will
recreate it next time it opens, but you will lose any customizations you may
have made to the toolbar.
2. Disable all add-ins. If PPT then opens correctly (that is, not in Safe
Mode), then you can enable each add-in one at a time until you isolate the
problem add-in. http://www.pptfaq.com/FAQ00655.htm will help you determine
what add-ins are loaded.