Windows Media Player cannot play the file because the required video codec is not installed on your computer.

I learned to today that Windows Media Player 12 does not come with any codecs installed and thus it may give you this charming error (as listed above). Some links to codecs I uncovered are:

1. http://www.divx.com/en/software/divx
2. http://www.xvid.org/Downloads.15.0.html
3. https://www1.gotomeeting.com/codec?Portal=www.gotomeeting.com