I discovered by trial and error that my one .ogv video will not loop, but if I interchange a random .ogv video from wikipedia that one does loop, and they are both called .ogv. Why is this? Is the not-looping file corrupted? EDIT! I just had a breakthrough! I discovered if I view the webpage using my computer's version of the file (not-uploaded version), then it does loop! (I open index.html on my computer, and it is a relative URL) But! The version which is uploaded onto my web server does not loop. (I changed the relative URL to an absolute URL which points to the file on my server. I tried re-uploading it, but still does not loop. If someone has an answer to why this is and how I can fix it, I will be very grateful!