Quicktime player plays music videos but will not play movie trailers

Hhhmmmmm....that's odd. If this only happens when you are playing streaming video thru the web, then it could be that for some strange reason your Internet Explorer isn't kicking in QT for you to play the video. Check in Int Explorer under TOOLs, then INTERNET OPTIONS, then ADVANCED. Scroll down to MULTIMEDIA and make sure that there's check in the box that says 'PLAY VIDEOS IN WEB PAGES'. I'm not sure that's it but it's worth a peek.

If it happens only on certain web sites it could be that their server is down or at capacity. Check other web sites and see if it works. Maybe try right clicking on the link to the video and choose "save target as" and download the video. May play from your hard drive.

That's all I can think of, bro. If these things don't work, drop me another line w/ more info on where these videos are, their file types, etc. and I'll see what else I can come up with.

Good luck.