Storyline crashing when publishing mp4

I am trying to publish scenes from a course in Storyline as mp4 videos. Each time I try to publish, the publishing process runs then shows the output dialog window. I select the Open process and the folder opens but there is no mp4. I have looked through the files to see if it is elsewhere but to no avail.

I have published mp4 videos a few weeks back with no issues. I did perform an Articulate software update last week and am no Storyline v3.63.27443.0 . I wonder if the update might be the cause of this issue.

I am under a time crunch to get these videos published. If anyone has any insight on how to fix the problem, please let me know.

Mike