Motion 5.4 Video Error 703

I am running Motion 5.4 with a 2010 iMac with 16GB of ram, 512mb VRam. I have plenty of space to export the video. I get this error message "651 ((Error 10008f, 00:00:21;21 <<(Error 10110f, 2018-03-11 12-56-18.mp4 @ 00:00:00:00)>>))" every time I try to render a video. In the video it contains a mp4, but I don't know if that would change the problem.