IF your having trouble with seeing or hearing some downloaded movies
 

If some movie downloads wont play or have no sound you may not have the codec needed for that file. To update your media player codec's its best to get a compleat pack . The ones I find that are the most compleat and lets me watch most videos out there are the (XP codec pack) and the (K-Lite Codec pack) Just be carfull ware you download from to avoid addware.