emailing invoices suddenly not working

[HealthByNature]

Out of the blue I am unable to email an invoice to my customers. I have att.net mail and the SMTP setting has always been outbound.att.net

 

My email account and password are correctly entered.

 

I have also tried adding the port and putting in outbound.att.net:465

 

I thought perhaps ATT changed something, so I also tried using a gmail account, and same problem. I am saving the invoice as a .pdf and then manually attaching it to email, but that is a workaround that is more time-consuming. Anyone know a solution?

[A-men]

I have a similar problem, my invoices wont send anymore, it says "the recepients email wont allow emails recieved in this manor" i never had this problem before.