It's technically a container format so we have to know this so we don't lose time trying to find MP4 players. Here's more. http://en.wikipedia.org/wiki/MPEG-4_Part_14
So many MP4s will fail to play as noted by "The registered codecs for MPEG-4 Part 12-based files are published on the website of MP4 Registration authority (mp4ra.org),[22] but most of them are not widely supported by MP4 players."
I'm guessing you are using Desktop Movie from Falcosoft.
http://falcosoft.hu/softwares.html
They have a support forum but in short you place a shortcut to any app you want to start in the startup folder. As the startup folder has been around from at least 2000, I'll pause here as I would be duplicating the web.
But in parting I like to TRANSCODE VIDEO WITH HANDBRAKE (see google if you don't understand that phrase.)
Bob
I downloaded Desktop Movie onto my Windows 8.1 computer and it works great. Except that when I restart my computer I have to manually start the program and then select the movie I want as my desktop wallpaper. I've tried going into Task manager to see if the program could be enabled as a startup program, but I did not see it listed. Is there a way to enable it as a startup program so that it automatically plays the movie when I restart and log into my computer. Or is there another program (preferably free) that could accomplish this task? I should also mention, since some programs are only compatible with certain video formats, that the video I wish to use a the desktop wallpaper is in .mp4 format. Thanks

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