I have a problem running mpeg and avi clips in PowerPoint on my new computer (XP, Office 2000) - they show only as a white square when playing. They run fine in Windows Media Player and if I convert them to wmv they run fine in POwerpoint. I think (but not 100% sure) the problem started after installing Nero CD/DVD software (including player) - I've tried removing all Nero components (no help) and setting Nero to not be the default player for any kind of video (no help). I do not have Real player installed, and Quicktime is set to only play Mac stuff. I know PowerPoint uses MCI to play videos - has Nero changed this in some way. I've had a look at the MCI extensions in the registry but haven't really got a clue what I'm looking at or how to fix it. Not sure if it's relevant but I have no idea which Direct X i have. HELP!