need quicktime 7.5.5

iTunes 10.5.1 requires Quicktime 7.6 or later. Here is the most up to date QT (7.7) to use with Leopard: http://support.apple.com/kb/DL761

I am on 10.5.8 and I have the same message showing up… I've done all the software updates that my Mac can find, and I've downloaded & installed the latest QuickTime version from your linke above (it's 7.7 now)… After installing this (which required a restart), I am still receiving this message when trying to launch iTunes. The only other thing I can think to do is to download iTunes from Apple's site and try to install that (should be the latest version and with a quicktime installer it uses/requires as well, right?). I am trying that now… but, in case this doesn't work… I'd love to know if somoene else has had this problem and gotten it fixed. Thanks in advance.

After some research, I think this provides the answer: iTunes 10.4 for Mac: Older media files may require iTunes to reopen in 32-bit mode,

http://support.apple.com/kb/TS3771

That link was excellent! Thanks for the help! That seems to have fixed things for me, too. 🙂