QuickTime X No Longer Plays .MOV

OK, I'm having the exact same issue. Can't seem to play movies from Apple's Trailer site. Worked fine previously. Won't work even if I use the contextual menu and select "Open with QuickTime Player".

I have not installed anything recently and I definitely watched a trailer 2 days ago.

Things I've already tried:
Restarted - No change.
Reset Safari - No Change

Update: Just viewed a quicktime video on Geekbrief.tv, so the issue appears to be with the format the trailers are viewed in (assuming this is the .MOV per the original poster).

Message was edited by: kaioslider

OK, there's already a thread addressing this. Seems it's a url related issue with the site and not quicktime. I copied the link and pasted it in a new window, then corrected the error in the url:
changed http://movies.apple.com............ to http://www.apple.com

I'm having the same issue but I am already accessing the movie trailers via http://www.apple.com/trailers/. Depending on the movie trailer i select, I either get a QT icon with a question mark or the error message saying "you may need to install additional software..." I even tried to access the trailers via Front Row and still get the same message. Can you help?

I am having the same issue. I get the Quicktime logo with a question mark. The url seems fine. I have reset and restarted Safari and restarted the computer, but nothing is working. This happened last week, but when I reset Safari, it was fine. Any thoughts?

I'm having this problem with both Safari and Firefox. When I try to watch a standard clip from the Apple Trailers site I get the Quicktime logo with a question mark. With HD clips it says "The movie “xxxxx.mov” can’t be opened. You may need to install additional software to open this type of file."

I had the same problem, log out, log in didn't fix it; restart didn't fix it. I then tried a Repair Permissions using Disk Utility and that fixed it for me. Hopefully that'll help you out as well.

Hi all above.
I've tried everything, and nothing seems to work. It's not life threatening to my work, but it's still bloody annoying. Arrrr!!!

Thank the Lord I found this site.

I rely on Apple trailers A LOT, and it's been all over the shop for weeks. The front page has random holes, some trailers aren't linked - the most recent problem is the unacceptable kind - one that makes you question your own machine.

It used to work like clockwork, but right now it's a mess. I hope they sort it out soon!!