Powerpoint?

[blueerica]

Okay... I'm looking for a few ideas on how I can fix a problem I'm having with a few powerpoints that my teacher has uploaded.

Here are the facts:

• The presentations were created using Office XP (2000?)
• I use Office 2003
• It shows as a PPT file, but when I click on Help, it suggests that it might not be a PPT file.
• The first slide previews in icon view when I'm looking through windows explorer
• I use Microsoft Vista, professor uses Microsoft XP
• I can open the un-openable files with the Computer Lab computers which use Office 2007
• I had no problems opening and reading Chapters 1-5. 6, 7, and 8 are "unreadable"
• Not having any problems with Powerpoint presentations from other classes.

Anyone have any ideas? I can't figure any compatibility issues, though my ability to open the files with one but not the other suggests that. The teacher says that she hasn't upgraded her Microsoft Office. So... hrm?

Helpz!