wpa.dbl

Your PC's note to itself that Windows has been properly activated is stored in two little files called Wpa.dbl and Wpa.bak. (They're in your My ComputerLocal Disk (C:)WindowsSystem32 folder.) If you ever decide to replace your hard drive, back up these little files before you remove your original drive. (Copy them onto a floppy, for example.)

Then, after installing the new hard drive and installing Windows XP onto it, copy the Wpa.dbl and Wpa.bak files into exactly the same folder. Windows XP will be perfectly content that it's running on a legitimate, properly activated computer.