Authentication is required for relay

[rehan]

NOTE : Personal identification has been replaced by bogus values.


Hello Forum Members,

I am facing issue of SMTP authenticatiion failure while trying to relay mails thru my ISP smtp server (99.99.18.19)

My local zimbra server was communication very well with ISP server acting as smart host using SMTP authentication.

One fine day the relay started to fail. As per my knowledge, no change whatsoever was made to the Zimbra or to the CentOS.

To set the authentication relay, i had successfully followed the below article :
Outgoing SMTP Authentication - Zimbra :: Wiki


When the issue started, i reapplied all the commands mentioned in the above article, but was of no help.

User name and password used for SMTP authentication had been verified by logging into the mailbox using Webmail.

Any help in this regards would be highly appreciated.

The actual error message , while trying to send mails out is as below :

<username@hotmail.com>: host 99.99.18.19 [99.99.18.19] said: 550
Authentication is required for relay (in reply to RCPT TO command)


Thanks in advance.
Rehan

[uxbod]

Have you asked your ISP to check their logfiles as why they are not authenticating you any more ?

[rehan]

Originally Posted by uxbod

Have you asked your ISP to check their logfiles as why they are not authenticating you any more ?

Thanks very much for you rprompt reply.

YES, this was the first thing i did when the issue started.
As per ISP, they are not blocking us in any way.

He suggested to check this by configuring Outlook / Outlook Express and use the same account name and password for SMTP authentication and then send a email to outside domain.

The above worked very well.

So the username & password used in Outlook / Outlook Express works but when used in conjuction with Postfix fails for some reason.

This is annoying me from some time.

Thanks
Rehan

[uxbod]

Does the following return your username and password

su - zimbra
postmap -q mailrelay.example.com /opt/zimbra/conf/relay_password

When you performed the reload of Postfix were any errors reported ?

[rehan]

Originally Posted by uxbod

Does the following return your username and password

su - zimbra
postmap -q mailrelay.example.com /opt/zimbra/conf/relay_password

When you performed the reload of Postfix were any errors reported ?

Yes, i get the proper user name and password by running the above command.
Also i dont get any errors while reloading postfix.

Thanks
Rehan