For early computers, the XP install disc or recovery disc came with service pack 1 or 2. Unfortunately, Windows XP’s latest and last version is Service Pack 3.   People who format and reinstall XP run into various problems because of this Service Pack issue.  This biggest issue is that an installation ID can not be generated when trying to re-register the computer.  A work around for this problem would be to download and install service Pack 3. Below you will find the steps on how to get this done:

1. Download windows xp service pack 3 from a working computer and save it to a USB flash drive

http://www.microsoft.com/download/en/details.aspx?displaylang=en&id=24

2. boot the XP computer to "safe mode only"

3. Run the .exe file in Command Prompt.  The file should be where you saved it on your flash drive.

4. Reboot the computer into "normal mode" and now you have an installation ID