Thanks for reply. I have now tried restoring the InDesign preferences, and that did not work. How can I tell, if the iMovie have created an invalid MP4 format, and how can I make sure, that it is valid?
I have the tried using the Adobe Media Encoder, but the mp4 is not on the format-list? I have F4V, FLV, H264, H264 (legacy) and MP3. Do I need something extra in the Adobe Media Encoder to make the MP4 files?
Again, thank you for your help :-)