Today I´ve installed a new patch from the Microsoft Update site. After rebooting my computer XP tolds me that I have to activate XP!!!! But why? I´ve acitivated it 1 or 2 months ago after the fresh installing.

Allright, I agreed the activation via Internet and the registration told me: Your product key is to often in use, you have to get a new registration key via the phone!!
A phoned with them and no problem, I got my key and XP is running now..... But why to activated XP again? I hadn´t changed any hardware or something like that. Have anybody an idea?