"Error loading media: File could not be played" in IE11
We have been receiving reports of the above error message but only in IE11 and only when accessing our website off campus (we're a university). The problem affects video (mp4) and audio (mp3) All other other web browsers work fine, on and off campus, and even IE11 works when viewing on campus. We encode our video to iOS compatible h264 mp4 using Handbrake and always with the 'web optimized' option checked. Xenu reports mp4 mime type as video/mp4 and mp3 as audio/mpeg.
We use HTML5 as the primary rendering mode. When I switch primary rendering mode from HTML5 to Flash the videos sometimes work in IE11 off campus but even when they do work I get the spinning wheel icon in centre of the player for a long time - a couple of minutes or more - before the video begins playing.
I can understand why there might be a problem with IE11 but not the cause of the problem. What I cannot get my head around is why it is only affecting users off campus.
Any help would be greatly appreciated.