In my experience Flash 8 was never able to successfully export to Quicktime, no matter what you did.
Flash CS3 is the first version of Flash where this export option actually worked.
I recommend one of two things:
1. Export to AVI, uncompressed. You will end up with a very large file, but there are a panoply of software out there that can convert an AVI to MOV, or even MP4
2. Download the trial for Flash CS4, open your project in there and export to quicktime.
Thanks for your reply, Ross. Unfortunately, I can't export to AVI because I have a Mac and as far as I can tell, that option is not available on Macs (at least, it's not available on my machine).
I have tried downloading the trial version of CS4 and exporting to QuickTime from there, but ran into another problem. In all of the videos I exported, the audio was so badly out of sync with the video that the movie was worthless. Any insight on this problem would also be greatly appreciated.
The weird thing is that I know I've gotten the Export to Quicktime (or QuickTime Video) function to work at least once in the past, with a different file (and I have the video to prove it). But now trying to export to QuickTime the very same file causes an error.
Export from flash 8 as Quicktime Video. The other option (just quicktime) doesn't export properly and never has for mac OR pc users. AND sad to say, has been unfortunately dropped in later versions of flash when adobe took it over. Quicktime video is basically the equivalent of export as AVI for pc and IT WORKS! Sure wish they would bring that export option back because its going to screw up a lot of peoples television production workflow.