1000 FAQs, 500 tutorials and explanatory videos. Here, there are only solutions!
Error: "The following addresses had permanent fatal errors" from mailer-daemon@...
Open the mailer-daemon message to find the reason of the delivery failure.
If the message was sent to several recipients, you should usually find the address that failed in the following lines :
----- The following addresses had permanent fatal errors -----
(reason: 550 Host unknown)
----- Transcript of session follows -----
550 5.1.2 <firstname.lastname@example.org>...
Host unknown (Name server: abc.xxx: host not found)
Link to this FAQ: