Good Day I clicked on a web page link and claws-mail opened a compose window. I completed the message and sent it off on it's merry way. The message was returned with, "The following message to <Dr.???> was undeliverable. The reason for the problem: 5.1.1 - Bad destination email address 'invalid domain "": no dot found' The exact address (with substituted question marks) was, " Dr. ???, DVM, MS, MPP <???@???.ca> " I checked the accuracy of the address and resent it. The message bounced back to me again. I edited the address to, " Dr. ??? <???@???.ca>" and it went through. Something in the address is confusing the address formatter. Hope this helps.
The string: Dr. ???, DVM, MS, MPP <???@???.ca> is not valid as a single address because ',' is a character that must be quoted to be part of the address¹. The single address in the mailto link it should have been written as: "Dr. ???, DVM, MS, MPP" <???@???.ca> Otherwise it's just a list of four addresses: Dr. ??? DVM MS MPP <???@???.ca> Which Claws Mail must handle as given because they are valid addresses, although some doesn't exist, hence the error you saw. ¹http://tools.ietf.org/html/rfc5322#section-3.2.3