I've seen this. It was (again) the codec issues. I decline from writing in depth what a codec is but when I see video playback issues I look at codecs and for color sometimes the video drivers.
I have never found this to be a "conflict between Windows 7 and Powerpoint."
Sadly I think this may be of no help since I don't supply a direct fix. I'll have to write for you to tell what CODEC that video is using. Again, since what a codec is, is widely discussed I won't repeat that here but will note I use the GSPOT CODEC APPLIANCE if I need to investigate what codec a video file is using.
I build a lot of Powerpoint presentations with embedded video.
I had been using Windows XP and Microsoft Office Powerpoint 2007.
Recently I got a new Toshiba laptop running Windows 7. I upgraded to Powerpoint 2010.
When creating presentations with embedded videos...the videos come out with a heavy blue tint to them. Presentations built on the old XP machine look fine on that computer -- but when played using the Windows 7 they have this weird look.
Presentations built on the lap top running Windows 7 also have this weird tint if later played on an XP machine.
Seems to me there must be some conflict between Windows 7 and Powerpoint -- but I have not been able to find a workaround.
Microsoft's user forums have been no help. Suggestions please?