Jerky playback of wmv file

I have Windows XP with Service Pack 2 installed on my computer. I was using a WMV file which was playing properly for almost a year now and the same I use for powerpoint presentation but all of a sudden it started playing jerky, however, the audio plays fine but the video starts and stops at random interval. When I checked in Task Manager then Windows Media Player shows that it is utilizing 50-60% CPU when playing the movie. I am running Norton 360 antivirus on my computer. I have even tried to upgrade to the latest Windows Media Player 11 version but to no avail. Does anyone know what should I do to get this wmv file to run back again properly? Thank you.

Have you tried playing the same wmv file in some other players like VLC media player? Also, did you try to install any codecs that might be required for the video file type, in order to play it properly. Try to also uninstall and reinstall the graphics driver and see if that helps. Please report us back again if this troubleshooting method is not working for you.

I did whatever you said but still nothing is working. I was now trying to use PowerPoint Viewer but still the playback is jerky but the buffering thing seems to fix the issue. But still that didnt help me because I am not able to buffer the video during the presentation that I have made. Any other solution do you have?

By the way I also tried to disable the Norton 360 antivirus on my computer but still the video file is jerky. Thanks for any help

I think that the problem is due to the lack of system cache for buffering in your computer. So try to go to Control Panel >> then System >> Advanced >> Performance >> Settings >> Advanced >> and finally Memory usage. Here check to see that if it is set to Programs then change it to System cache. After that restart the computer and if all is well then the video will play properly.

Thanks for the replies. I tried your solution but that didnt help me either and there is no difference that I can note, the wmv is still starting with some jerky movements.