The message that appears for you on the video container indicates the following and prompts some of these conclusions:
- The system is able to target the container "movie" and attempt to load the video into it.
- The browser video sub-system fails to play the video and is alerting you to this fact.
- It is possible that the file Movie1.mp4" is not actually in the location that you expect in the export tree.
- It is also possible that the video is not in a format your browser can play. Sometimes re-encoding the video using a program like Handbrake can make the video playable.
- It is also possible that everything on your computer is set up fine, but the export does not play the video because it requires a server to be sending the video stream. If that is true, then turning on the "Web Server" in the "Preview" page of the export process and then opening the export should display the video.
- Please note that a browser may refuse to play an mp4 unless the user has had some previous interaction with the web page. Therefore, loading a video on load page for the first page of an export may not always work, especially if it contains audio and video feeds (which is the case with your video).
- Trying a different video is sometimes another way to troubleshoot your setup versus the failure of single file (mp4).