I am having some difficulties setting up my iPhone and OS X email clients.
On the phone, emails can be received, but not sent. On the desktop, setting up the mail account manually fails with a “SASL PLAIN authentication failed” message and sending from the phone an aborted authentication failed “method=PLAIN” message in the /var/log/mail.log. I can send and receive just fine through the web client (Roundcube).
I’ve scoured as many forum topics and websites as I could and I’ve seen various different explanations - not the least of which being that it takes some time for DNS changes to propagate. I’m stumped.
Any advice for where to look for clues next?