Some emails I send (from php) are returned by hotmail with this message:
<email@example.com>: User and password not set, continuing without authentication. 18.104.22.168 does not like recipient. Remote host said: 550 Requested action not taken: mailbox unavailable Giving up on 22.214.171.124.
I understand that the recipient has no mailbox. But what does that mean:
"User and password not set, continuing without authentication."
And what can I do to avoid it?
I use linux/qmail.
EDIT : I am not using hotmail to send emails. I am sending emails to some hotmail users.