By default, if you’re running the latest Windows Media Player there is no need of additional codecs to play those High Definition Videos.

Believe it or not, it is the codecs themselves that keeping you away from playing HD Videos properly.

Problem: HD Videos can’t play properly in Windows Media Player

Solution: You need to identify which codec may have caused this, as I said by default you shouldn’t have problem playing HD Videos, all the lacks should be blamed on codecs.

A codec is a device or program capable of encoding and/or decoding a digital data stream or signal

In many cases, codecs are installed unawarely. For example in my case, I’ve installed Adobe Premier CS4 along with the codec package and guess what? My Windows Media Player couldn’t play any of the HD Videos.

By uninstalling the codec package, you’ll be able to fix this, however you’ll have less options in encoding or decoding video in Adobe Premier.