basically magic jellybean will let you view and change your encrypted cdkey from within windows, though you can only change the cd key in xp. You can not change the key in 2000 or 2003 with mjb. You can also view change the cd key in 98 and me.
here is an example, here in the shop I will get a pc in that has a
coa ( cd key , 5 groups of 5 alpha-numeric characters) on the side.
I BU the data then do a WAR ( wipe and reload ) of the HD.
I install xp with a " slipstreamed " version of xp that needs no intervention or user imput ( except for at the end of the text mode part, where xp asks to format ) . So the slipstream xp installs a cdkey, my cdkey. So after xp is installed I use MJB to exchange my cdkey for the one on the side, sometimes this does not work, especially if it is an OEM pc. Sometimes it does and it goes to the part where xp forces you to call and get a setting code that is ok. They ask you twenty question, then give you the setting code.