Disable Windows XP Activation

1.Open your regedit RUN > REGEDIT

2.Find key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\WindowsNT\CurrentVersion\WPAEvents

3.Look for the string OOBETimer

4.Double click. Then change all content with this one, FF D5 71 D6 8B 6A 8D 6F D5 33 93 FD

5.Right Click on WPAEvents(Regedit)and choose Permissions.

6.Window will show up, click to System and check all of Deny Listbox

7.Restart Your PC

However, if you are still prompted to activate Windows and unable log into the Desktop. You may checkout this hack. It worked for me.