Office 2000/02 random spoolss.dll error

We have Office 2000 Pro and Office Pro XP, about half of the users are using each. We are having very strange printer errors which appear to be completely random. We have 2 Canon ImageRunner multifunction machines and a couple HP’s (8100, 4050). spoolss.dll and spool32 errors as well as unexpected delivery of the print job to the last users mailbox (a feature of the Canon ImageRunner) who printed a shared wrkbook using Excel.

Any ideas?? Thanks!!