I try to upload videos into my computer and every time I try to play them on Windows Media Player a message comes up telling me there was a failure in downloading the codec. The file name would be on the right-hand menu of the player instead there would be an orange exclamation mark on the name and it only plays the sound but not the video itself. I use the Samsung VLUU NV15. Is it a problem with my camera or is it a simple problem with the settings on my computer? And by the way, what is a codec?