A German computer magazine, CT, recently revealed a way to change Windows XP Home to Pro. You only need to change the Installation File in two bytes. We cannot guarantee the effectiveness of this method. However, we may be able to tell you how it works and its flaws.
First, make sure that you cannot modify the installed Windows operating system, but can only perform operations on the installation CD (or resume the CD provided by the PC manufacturer)
Procedure:
1. Copy the Windows XP installation CD root directory and i386 directory to your hard disk.
2. Obtain the Boot Sector Program (BootSector) in the installation CD of Windows XP)
3. Change the i386/Setupreg. Two bytes of hiv:
A. Open Registry Editor
B. Highlight HKEY_LOCAL_MACHINE
C. Menu: File-> Load Structure-> i386/Setupreg. hiv
D. Assign an arbitrary name to the imported structure e.g. "Homekey"
E. Enter HKEY_LOCAL_MACHINE/Homekey/ControlSet001/Services/setupdd
F. Edit the binary "Default", change "01" to "00", and then change "02 to 00"
G. Highlight "Homekey" and select menu: File-> unload structure
4. Burn your new XP Pro installation CD
5. Install Windows XP Pro. The Home serial number is still valid.
Note: you cannot install SP2 in such a Windows XP Pro system. You can only use an integrated SP2 installation disk.
The Chinese XP directory may be different from the German version.