The USB ports on my Toshiba Satellite laptop (with XP SP2) have stopped
recognising anything plugged in to them: external hard drive (which does get
power), optical mouse, flash drive. Also, when I try to uninstall the mouse
in Device Manager, or scan for Plug & Play hardware it stops responding and
has to be stopped via Task Manager.

I have had a number of automatic updates installed recently, but thought I
had restored the system to before that, yet the problem remains.

Any suggestions?