I'm having problems with my videos my new Windows 8.1. Every-time I click on the video I want to watch, but it keep coming up as an Media Player Error (picture shown below):
Can't say for sure, but all those mpegs might have been created with an old codec that is not compatible with your current version of Windows Media Player. Unfortunately, I don't use Windows Media Player anymore so I'm not going to suggest that you try and update the WMP codecs and/or download a 3rd-party codec pack to try and fix your issue; however, I will recommend that you give VLC Media Player a try to see if that will play your videos. Good luck.