Hi Peter,
This problem may occur if a file that the Windows Product Activation (WPA) requires is damaged or missing. This behavior occurs if one or both of the following conditions are true:
- A third-party backup utility or an antivirus program interferes with the installation of Windows XP.
- A file that WPA requires is manually modified.
This kind of concern is being handled by our TechNet support. For advance troublshooting steps, we recommend that you post your concern to the TechNet forums using the link below:
Should you need further assistance, feel free to post anytime.