Because it is still valid for those 25 days. If it was invalid, say with a pirated key then it would be invalid. Yours is just an non-activated XP inside the grace period and therefore valid.
(speak to some lawyer about this?)
My computer receintly crashed due to a virus so I decided to wipe the slate clean & start over.I have 2 hard drives.The one with the XP Pro was the one effected so I reinstalled the software but when I got to the point the put in the activation key I had no idea what I did with it.So I have put it off until I do.I have 25 days left.Yet when I go to the microsoft website I can go to the validation site & it is validated as being good.Why will it do this without the key? Do I need the key if it shows as being valid?Thanks.