Changing the login screen for your windows XP is a nice trick that would impress your friends and younger brothers and sisters very much!
You will need a specific version of logonui.exe for whichever version of XP you are using, be it XP, XP SP1 or XP SP2 (Though most SP1 ones should work in SP2). Using a wrong version will cause a lockup buring the boot seqeunce!
Check out [http://www.themexp.org/] for many llogonui.exe. Including the Original Ones
1. In Explorer, browse to C:\Windows\System32 and find the file named "logonui.exe".
2. Rename "logonui.exe" to "logonui.exe.bak". This way if anything messes up...you have a backup.
3. Place your new login in C:\WINDOWS\SYSTEM32 and rename it to logonui.exe.
4. That's it! Now when you log off your new login screen will be there.
Also a few programs can change the login screen for you!
Logon Loader at [http://logonloader.danielmilner.com/]
LogonStudio at [http://www.stardock.com/products/logonstudio/download.html]
AGAIN, ALLWAYS MAKE A BACKUP OF LOGONUI.EXE, if anything goes rwong you can replace the file again in safe mode!

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