How to perform a repair install from XP Home OEM to XP Pro Volume License

I have a client who recently moved to active directory.  They found out however that they had two stations with XP home edition.  They opted to upgrade them to xp pro but did not want a fresh installation.  After some struggling I discovered that XP Home did not allow a repair install “upgrade” to XP Pro Volume license edition.  After a bit of digging I adapted a set of instructions found here to get the job done.

First these instruction assume the system boots.   Boot into windows and launch regedit.

Navigate to:  HKEY_LOCAL_MACHINE/SYSTEM/ControlSet00X/Control/ProductOptionsLook for *ControlSet00x  where x is the highest number

  1. Delete the ProductSuite registry key.
  2. Then, create a new DWORD value and named it as Brand.
  3. Set the “Brand” value data as 0.
  4. Reboot the system.
  5. On boot up after the BIOS screen, press F8 to display Windows XP Startup Menu.
  6. Choose Last Known Good Configuration and hit Enter.

Once the system boots into windows right click on my computer and choose properties – verify the system reports itself as Windows XP Professional under the General tab.

Now reboot to your Windows XP Pro volume license CD and the option to perform a repair install should now be available. (It’s necessary to do the repair install because even though the prior step causes the system to report as XP pro it is missing most of the critical components that make pro . . . pro.)