Rated 5 out of 5 stars

This works for the old MS Vista Windows Media Player. You can get directed to install a converter plug in, to convert the mp4 video to wmp. Wait for the conversion to happen (the conversion box disappears).
Then look for your video going through Start-Explore-User (double click to expand)-dwhelper (yellow folder). Move the video to your video section.

This review is for a previous version of the add-on (4.9.14).