TVs are poor file players. You can fix filenames but encoding seems to really push user capabilities.
The rule for file name is KISS (keep it simple simon.)
As to encoding I use VLC Player to examine the files that work and the ones that don't play. THIS IS DONE AFTER YOU FIX FILENAME AND EXTENSION ISSUES. Again, a TV is not a PC so you have to fix things you won't on a PC.
Have downloaded many videos to youtube to be viewed later on the VIZIO D24-D1 . Recently I've found that some video filenames can be seen on the USB drive... filename can be seen but not played... other videos downloaded to a USB drive via desktop and seen but not seen when inserted in the TV USB Port. All downloaded files can be viewed when USB drive is inserted in the desktop. Looking for guidance on how one troubleshoots such an issue.

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