You want be able to roll back to wmp9, You'll have to uninstall wmp10, the install wmp9.
You should be able to install wmp9 from the windows update website.
To uninstall: Start/Control Panel/ Add Remove Programs/highlight the entry Windows Media Player 10, then click the add/remove button and follow the direction on the screen. Then go to Windows update site to install wmp9.
Best of Luck
I'd like to revert to WMP9, could anybody tell me how to uninstall WMP10, I've tried Rollback and System Restore unsuccessfully.My OS is XP Pro. Cheers.

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