We do the same thing.  Not to sound unsympathetic to the OP, but software doesn't always work correctly.  There should be some kind of in house check in place to make sure things that are being sent out of your office are correct instead of just trusting that the software will do it right every time. There seems to be some kind of issues with tax forms every year (and not just with EasyACCT, we know other offices that have had repeated issues with other software companies as well).

That said, if that's really how customer support handled it that is obviously unacceptable.  We have never had anyone flat out hang up on us, but the go to line from them is usually "We are aware of the problem and are working on a fix, but we don't have an estimated timeframe at this time" which is super annoying.