Are you saving the video as a Reference only to the external video, or importing it completely into the file?
If stored only as a reference, then depending on how you are hosting the file, the host/server must have full read permissions and access to the mounted volume where the video file resides.
In cases like this, the video needs to imported into the container, not stored as a reference unless you intend to maintain a system-wide directory for referenced file content.
I'm not sure but must be in reference. If I right click in the field and import a Quicktime, is that a reference to my movie? Isn't that the only way to view the movie in Filemaker without having a specific upload area and a webviewer? I'm confused as to how to specify for th end user to upload their quicktime for everyone to be able to see it in the container.
Thanks for your answer and I look forward to hearing from you again.
IIRC movies are only stored as references in FMP 11, so most likely the movie file is sitting on your computer's hard disk, inaccessible to anybody else.
FMS 12 solves this with the interactive container fields... otherwise try SuperContainer.