Mac mail coming back
Very strange been sending emails to a friend but all of a sudden they are coming back saying mail demeon permanent error....But they can send an email to me and its only this one person. We have talked about it she does not know why...If I send from my iPhone its okay.. But from iMac they keep coming back...Is it her end? She does not know either...and why just her...
iMac 27″ 5K, macOS 10.14