I broke Software Installer on my X31

[kreed]

Gentle persons:

So there I was, "cleaning" my X31 of cruft in the file system and the registry left over from old IBM updates and I got into a state where the Software Installer won't start. It displays a message that says it is for IBM/Lenovo systems only and then quits. (And, before you ask, the answer is "yes, the BIOS has the requisite model and serial number information in it.")

At first I kept getting the same result after rolling back the system to a previous state, but after a reboot (or maybe two!), Software Installer started working again.

Does anyone know what Software Installer is choking on?

Regards,
Kent