Sage 300 Error: Causes, Fixes, and Practical Ways to Avoid Them If there's something which can ruin a working day, it's a Sage 300 error popping up as you prepare reports to be run, invoices to send, or entries for the month to finish. Sage 300 is powerful, certain, but just like any other program that manages databases, accounting and network communication it is not immune to errors. And, when they do, they are usually at the most awkward timings. ...