Possible to upload mp4 video files to EPM Workspace??

I'm trying a test to add a video training video to our EPM Workspace Shared Workspace Pages so it can be viewed by all users.  I found some steps on adding the MIME type required for mp4.  Then I uploaded the video file and it seemed to work.  But now when I try to watch the video, Windows Media Player gives an error: "Windows Media Player cannot play the file. The Player might not support the file type or might not support the codec that was used to compress the file."

The video works when viewed in Windows Media Player otherwise (just opening the file from my local drive).  So is it not possible to add videos to Workspace?  The version we're on is 11.1.2.3.500.17, and the video I recorded myself with Skype for Business.