HELP I am using Windows Media Player 10 or Windows Media Center on my Dell E310. They WILL NOT play a store bought DVD. They say "no decoder installed or decoder malfunctioning". I installed ANYDVD Decoder. Still the same! I also purchased another decoder with same results before this and removed it. I have tried everything--help---The WMP does not recognize the DVD being in the drive. It just says "no decoder present". Music CD's and the like work fine.