For all the Windows 7 64 bit + After Effects CS5 users out there:
I had the same problems as many others on the web, the; “QuickTime is not installed on this system…” Bug.
I’m using Windows 7 on a 64 bit pc, which adds an extra “Program Files” Folder for 32 bit app’s.
But I fixed it by just simpely uninstalling Quicktime completely and reinstalling it to the 64 bits “Program Files” Folder. (not the Program Files 86X Folder)
It got After Effects with Quicktime running directly after doing this.