One was created using rebox on Windows 7, one was created using mp4tools on a Mac.

The USB drive used is an HFS formatted one, which has many WMV files over 4GB so I don't think it's a file size issue:

http://dl.dropbox.com/u/2213114/Bridesmaids%20%282011%29.txt

http://dl.dropbox.com/u/2213114/Dirty%20Dancing%20%281987%29.txt