look in Add-Remove Programs to see if Media Player 10 is listed....if so, remove/uninstall it.
Then go to Windows Setup or Add Components to get the list of everything XP defaulted to installing before, and if Media Player is checked off, uncheck it so the original gets uninstalled, too.
Reboot the computer, and then go back to Add Components and reinstall it (it will be the version that came with XP and should now work once you reboot the computer again)
TONI
Ok, i am running XP on a dell 2650. A few weeks ago i installed SP2 on my computer, and when i restarted it i found that it was painstakingly slow. I promtly removed SP2 and reverted back to SP1. After removing SP2 i attempted to optimize my performance, which included deleting the roll back settings (this will be important later). Yesterday i tried to open Windows media player (10), and i recieved an error reading: "Internal application error" and the media player didnt open. I then attempted to roll back to version 9, and obviously it didnt work (i had deleted the rollback settings). I then attempted to reload media player 10, and about 3/4 of the way through the install it stopped and an error that read: "installation has failed" was displayed. How can i fix this problem?
P.S. media player worked fine before i installed SP2

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