Unable to play video files in Windows Media Player after downloading with Coursera-Downloader Extension

[ghost]

The problem:
I am unable to play video files on Windows Media Player after using the Coursera-Downloader extension to batch download files.

I receive the following error message:
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.

If I download the same video files from Coursera one-by-one, they play with no problems.

I suspect the problem arises due to how the Coursera-Downloader extension compresses or otherwise modifies files prior to downloading them to my machine.

What I am using:
Chrome Version 44.0.2403.157 m
Windows 7 Home Premium with SP 1

I've attached a screenshot of what I see by opening the two different versions of a downloaded video.

Thanks for any help you may offer!