Exported .mov opens fine when transferred via flash-drive, but not via FTP download

I’ve exported a flash movie to .mov which opens in Quicktime from my desktop without a problem. I’ve since uploaded it to my FTP site for distribution to other people. When others try to open it they get a “The movie could not be opened” message.

I downloaded it to my wife’s computer and got the same message. Funny thing is, that when I transfer the file to her computer via flash-drive it opens just fine.

Any ideas? Any help would be appreciated.

Thanks,

viddie