You have to disable hardware acceleration for it to work. Two ways to do it:
1. If you have Windows Media Player 9 or higher, go to tools, options, then click on the performance tab. Pull the video acceleration slider all the way to the left.
2. Disable it globally. Right click your desktop then choose properties. Choose the settings tab and click advanced. Click on the troubleshooting tab and pull the hardware acceleration slider all the way to the left.
Once that you’re done taking your screenshots remember to reenable hardware acceleration, since disabling it usually produces a performance hit.
P.S: If you like you can try Media Player Classic for taking stills of movies (no disabling of hardware acceleration needed). Just press F5 while you play. The stills are automatically saved sequentially in your 'My Pictures' folder.
Media Player Classic: http://www.gabest.org
Well this is a change of pace, but i got a problem with stuff im trying to do on my computer. Im trying to make a backround by taking a print screen of a video file on windows media player, but every time i try it, the picture shows up in in photoshop, but whenever i try to set it as my backround the picture turns completely black. Any suggestions?