I got this warning during bootup just after BIOS screen.

2200: Machine Type and Serial Number are invalid


After reading the forums i downloaded the latest Lenovo Maintenance diskett version 1.79 and boot from that and did what the manual said and entered the 16-character number from the back of the laptop, the system said that the number was already in the EEPROM??!!?

What do i need to change to get rid of that warning? i thought i just needed to do the above?

Remove it from EProm and reprogram it. Check BIOS first to see what's displayed ..

Thanks mate, i deleted and re-entered, working great now.

Just to mention that the latest version of the Maintenance Utility supports booting from a USB flash stick which i did so you don't need a diskette anymore as before.