I'm trying to resolve a customer's problem without a wipe and reload of windows. Ideas would be appreciated. Customer has a Dell Dimension 4300 with an NVidia MX/400 card, running WinXP Home SP2. PowerDVD 5 is installed, as well as the program patch that is supposed to resolve various issues with PowerDVD and Windows XP. When a DVD is inserted, PowerDVD opens, and sound will play, but there is no video and scanning forward/backward is disabled. I attempted to open the DVD in WMP, and recieve this error message: '%1 is not a valid Win32 application.' I downloaded Media Player Classic and attempted ot play the DVD from there. I recieved this error message: 'Failed to query the necessary interfaces for DVD playback.' I installed ffdshow and k-lite to be certaint there were no missing codecs. I have uninstalled the Nvidia drivers (using Nasty File Remover to be sure I got it all) and reinstalled the lastest drivers. I have uninstalled PowerDVD 5 and reinstalled. I have tried multiple DVDs. Still the problem persists. I cannot play DVDs from any application. THe customer wants their computer back by tomorrow. I've come as far as my experience and Google will take me. Are there any more experienced suggestions or ideas I haven't yet tried? Thank you.