I am having the same issues with QB Pro Plus 2021 crashing when trying to email invoices.     I have contacted customer support multiple times that ultimately reroutes me back to this forum, problem unresolved.  Evidently, this appears to be an ongoing issue that I would expect that Intuit would have already addressed and fixed by now.    What is the hold up?    An accounting software with key features of invoicing and receiving payments that does not work is useless and beyond frustrating.