If I want to send mail by external account.
I mean receiver can see external account in "sent by :".
example I have email@example.com -----> main
firstname.lastname@example.org------> external account
Now I send mail using email@example.com but receiver see firstname.lastname@example.org
in "sent by" ,How I do for receiver see email@example.com in "sent by"?
thank you for answer.