All those itchy hands or had automatic updates, went to upgrade and facing problems with WMP11... you've got some help.
Please note that this only applies to XP. If you are using other systems (by right you shouldn't, whatever way you got WMP11 installed, I don't know how to fix).
Another note: Please do not run CCleaner, CleanUp!, ATF Cleaner or any other cleanup programs. If you do so, then you won't be able to roll back. Do it after you've successfully rolled back.Part 1Please also make sure that you are part of the Administrators group, whether or not your logged in name is Administrators.
To check, go to Start > Control Panel > User Accounts.
Your logged on nick should be under Computer Administrators as shown in the picture below (blue box):

If you can't find User Accounts icon, look on your left.
You will see Control Panel with two arrows pointing upwards.
Click on
Change to Classic View (see image below, brown box).

Now, if you are not part of the Administrators group and is using XP Professional, there's a way to get pass.
Go to Start > Log Off. Select Log Off, don't switch user.
Press Ctrl + Alt + Del twice.
You will shown a log in box.
Type in
administratorThe password should be blank.
Press Enter to log in.
For XP Home users, go to Start > Shut Down.
Wait for 30 seconds. Then boot up your system again. When you see a screen asking you to press some buttons (Del or F2 or whatever), press F8. Keep pressing F8 till you get into a screen that shows you the Safe Mode option.
Use the up down arrows to select Safe Mode. Press Enter.
Wait for XP to load.
Once it starts, select the Administrator account, NOT your usual account.
The rollback starts now!
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Part 21. Disconnect all your portable music devices. Refer to the portable music guide provided by the manufacturer to find out how to safely remove them.
2. Go to Start > Control Panel > Add/Remove Programs
3. At the top right hand corner, tick
Show updates box (see image below, brown box)

4. Locate
Windows Media Player 11. Click on the
Remove (it may be Change/Remove, depending on your settings) button.
5. Click
OK when the dialog box prompts you.
6. You will be prompted to restart when everything has finished. Click on
Restart. If it doesn't prompt you, go to Start > Shutdown > Restart.
7. For XP Home non-administrator users, please repeat the above steps to get into the administrator account. For XP Professional non-administrator users, do the same as well.
8. Go to Start > Control Panel > Add/Remove Programs again.
9. Locate
Windows Media Format 11 Runtime. Click on the
Remove (it may be Change/Remove, depending on your settings) button.
10. A dialog box will prompt you again. Click
OK.
11. A second dialog box will open, asking you if you want to continue with the rollback. Click
OK.
12. Once it's completed, it will prompt you to restart. Click
Restart to restart your PC. If it doesn't, go to Start > Shutdown > Restart.
13. Non-administrative users, repeat part 1 to log in to log in as administrator.
14. Go to Start > Control Panel > Add/Remove Programs
15. Locate
Microsoft User-Mode Driver Framework Feature Pack 1.0.0. Click on the
Remove (it may be Change/Remove, depending on your settings) button.
16. You should see
Software Update Removal Wizard. Follow the instructions in the wizard.
17. Once done, you should see a confirmation box that is named
Wudf01000. Click
Yes and follow instructions. Once it's done, click
Finish.
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Other notes
If you encounter this error: C00D271D ( "A problem has occurred in the Digital Rights Management component. Contact Microsoft product support." ), install Windows Media Format 9.5 Runtime. For more details, refer to this MS Article.