Have you tried doing a restore to a point when it worked correctly?
It happens whenever I try to play any video in all video players. I am running xp home with a athlon 64 2200 with 512mb of ram a sapphire 9600xt 256mb. All errors are stating that the files are causing the player to terminate in a unusual way. any help would be great, Room mate uses the computer for 4 days while I am out of town and he is computer illiterate. Worked when I left now it doen't I can only think he did something, and he is a drunk so asking him when the problems started is hopless.

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