Thanks for trying folks, but still no joy.
I tried uninstalling and rebooting, but once again windows reported that no driver was available to reinstall.
I would try the Vista compatibility trick, but I have to have the old file to start with, which doesn't seem to exist on any search.
I have already tried contacting Acer, but they just sent me the usual fixed answers on drivers from their site, none of which were any help.