How to deselect the Windows Messenger that comes preloaded with Windows XP?

Every time you load Windows XP, the Windows Messenger is loaded by default and there is no straightforward way to permanently disable it through the Control Panel or Messenger. The startup might offer you an option of deselecting the messenger from the list
of startup options, but its definitely not the end of it and some applications do override those settings, causing the Messenger to load at startup nonetheless. To permanently avoid the messenger from loading at startup, you should use the GPEDIT.MSC command. Click on Start, go to " Run " and enter " GPEDIT.MSC " and click on " OK ".

For "per machine" restriction, go to " Computer Configuration | Administrative Templates | Windows Components | Windows Messenger ". Change the settings as you wish; you can either disable Messenger completely by double clicking on " Do not allow Windows Messenger to run " and enabling the option (by default it is not configured). Or you can also select the second option

" Do not automatically start Windows Messenger initially " and enable that option to simply stop Messenger from loading during startup. Similarly, for "per user" restriction, go to " User Configuration | Administrative Templates | Windows Components | Windows Messenger "  and modify the settings according to your wish.