Tried to upgrade my BIOS on the weekend so that it would recognise larger hard disks. Result: Windows will no longer boot, giving some obscure error message about a device PLKSCNR. Google gives exactly one result for this search term -- apparently it may have something to do with the Plustek parallel-port scanner I have.
They suggest restoring an older registry copy. I'll try that and hope it works. If not, I'll have to reinstall Windows again. With the result that my registered shareware will become unregistered again, various programs will stop working until I reinstall them, etc.
Fortunately, the two programs I use most (MUA and news reader) store their configuration in good ol' text files, which can be backed up easily and which will not be deleted upon a reinstall.
What was the advantage of storing everything in the registry again?