Can’t remove XP print drivers

I have an XP workstation that prints to a Xerox Document Centre. The driver that’s installed is not the right one; the accounting pages are missing.

So I go into Start/Printers/File/Print Server and click the Drivers tab. The driver is there so I click remove. It then says:

“Cannot remove driver – Already in use”

The user that logs into this machine does not have this printer defined. Neither does Administrator.

How do I simply remove this driver so I can install the new one?

Thanks!