Maksym Watroba
Maksym Watroba voted up matrix hacker's answer
This error usually happens when you have a copy of xp (not the original one), and you install sp2 on your computer when online. You must either activate it or re-install you windows xp. Here is how you remove sp2. click me
Maksym Watroba
Maksym Watroba voted up Anonymous' answer
If you click on [Activate] (or something similar, I can't remember the exact wording) you should see an option to activate by phone. This will give you a toll-free number to dial, and will display a code which you have to punch into the phone.
Maksym Watroba
Maksym Watroba voted up Tris Fray Potter's answer

How do you define 'crazy'?  Am I crazy?  I don't know.  I have no way of knowing for sure whether or not I am crazy.  Even if I am diagnosed as crazy, there might be a new type of crazy that I am.  Everyone's different.