An upgrade to Windows XP Pro is a one-way ticket with no
uninstall option.  You'll have to reformat the drive and reinstall
XP Home "clean".

The Windows XP CD is bootable and contains all the tools necessary
to partition and format your drive.  Follow this procedure and allow
Windows XP to partition and format your drive:

1.    Open your BIOS and set your CD Drive as the first bootable device.
2.    Insert your Windows XP CD in the CD Drive and reboot your computer.
3.    You'll see a message to boot to the CD....follow the instructions.
4.    The setup menu will appear and you should elect to delete the existing
      Windows partitions, then create a new partition, then format the primary
      partition (preferably NTFS) and proceed to install Windows XP.

5.    Windows XP Clean Install:
      http://www.winsupersite.com/showcase/windowsxp_sg_clean.asp

6.    Accessing Motherboard BIOS
      http://www.michaelstevenstech.com/bios_manufacturer.htm

Greetings --

  The only way to change from WinXP Pro to WinXP Home is to format
the drive and start over.  There is no supported downgrade path or
technique.

   Simply boot from the WinXP installation CD.  You'll be offered the
opportunity to delete, create, and format partitions as part of the
installation process. (You may need to re-arrange the
order of boot devices in the PC's BIOS to boot from the CD.)

HOW TO Install Windows XP
http://support.microsoft.com/default.aspx?scid=KB;en-us;316941

http://www.michaelstevenstech.com/cleanxpinstall.html

http://www.webtree.ca/windowsxp/clean_install.htm

http://www.winsupersite.com/showcase/windowsxp_sg_clean.asp

   Of course, you'll want to back up any important data before
starting.

Bruce Chambers

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