postfix 550 550 #5.1.0 address rejected even when the email exists

Delivery to the following recipient failed permanently:

Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the recipient domain. We recommend contacting the other email provider for further information about the cause of this error. The error that the other server returned was: 550 550 #5.1.0 Address rejected (state 14).

anyway to fix this I have went to the postfix documentation and changed settings to 550 even when they said to change some values to 550 is still is not working

I assume “” is a domain you’re hosting? You might want to check /var/log/mail.log at the time the error occurs, which should contain more detail about what went wrong.

Feb 2 06:34:58 projectleeroy postfix/smtpd[18429]: connect from[]
Feb 2 06:35:00 projectleeroy postfix/smtpd[18429]: warning:[]: SASL LOGIN authentication failed: authentication failure

These are the error logs and its the SASL LOGIN authentication faild

can’t find anything usefull to help me


Well, you may want to double-check the username/password to use in the Edit Mail and FTP users screen.

Also, what is the format of your email login names – is it the default user.domain format, or is it using user@domain.tld for the email username?


I’m a bit confused here… Your initial post suggested that Google is having trouble delivering mail to one of your addresses, but the subsequent log entries suggest that one of your users is having trouble logging in to send out mail.

Can you reiterate please what exactly the problem is, and at which point you tested what and posted which log?