I bought a Toshiba Satellite L855 S5112 in March 2013 and it worked as I expected from this manufacturer-not a problem. But I fooled with it and videos stopped playing. I tried all of the troubleshooting ideas and finally did a system restore after I became annoyed and perceived other problems. I continued having the same problem, and now, after two PC refreshes, YouTube videos have stopped playing. I, obviously messed up and not the laptop manufacturer.So.no Webvideo from ANY source is playing. I would really appreciate a detailed approach to correcting this since I created it.