Mail server rejects your
login.
1.If you are using Gmail as mail server,
please turn on "Access for less secure
apps". Or enabling 2-Step Verification and
then create an "app password" for
scanner.
2.If you are using Gmail as mail server,
you can login on A place, at the same
time, someone uses your account to login
on B place. Gmail will reject someone's
login.
3. Please contact the administrator of mail
server.
Failed to login to Mail server.
1.Server requires authentication.
2.Check login name and password.
To, CC and BCC addresses
are empty.
Recipient mailbox may be
not available.
1. Check recipient’s addresses.
2. If mail server is Microsoft Exchange,
please check the settings on mail server,
is the IP of machine allowed to send mail?
Mail attachment size
exceeds Mail server's
limitation.
1. Check mailbox storage allocation.
Recipient address is not
correct.
532440
532553
532554
537554
From address is not correct.
HELO command is rejected.
Check "Host Name" and "domain name".