I am closing a business. I did a tutorial in imovie 09. The customer asked for a MPEG-4 movie. No problem! iMovie 09 does that. So, project finished. Exporting is becoming a headache. Exporting with Quicktime affects the resolution of the movie in such a way that is unacceptable. So I clicked "Share" to iTunes and the MPEG-4 with full resolution was made without loss of it. My customer tried opening the mv4 file in his modern Windows laptop (which showed as a MPEG-4 file) and noticed that he could not open the file in Windows Media Player. He only could open it on iTunes or Quicktime. An yet... it does not play fluently... it plays choppy. No apparent CPU issue... SIGH!!! As I dig in in desperation, I find out that Microsoft and Apple have different codecs for the single MPEG-4 type of file and their files won't play in their rival's OS. Isn't this frustrating? Help Anyone!!! I believe that the customer wants the file in MPEG-4 to transfer the movie file to a Macromedia Software of some sort and distribute it with his product. Thanks!