After installing the latest batch of Windows updates which are automatically down loaded, the ergonomic mouse ceased to be recognised. I had to resort to the Logitech or touchpad which both continued to be recognised.
By restoring the system back to a point immediately before the updates and then installing the updates one by one, I identified the problem as Vista update KB 938371. This update is required to install and uninstall Vista SP1.
Any ideas on how I can get my mouse recognised when Update KB 938371 is installed?