What is this error message?

Posted on 2004-10-21
Last Modified: 2013-12-15
I tried to setup pop3 server. My OS is Fedora 2.

Everything seems fine. But, if I sent an email to the user of the POP3 server, it did not reach there. I checked in the mail log and the following error messages appeared:

SYSERR(root): config error: mail loops back to me (MX problem?) did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA
DSN: Local configuration error

Any idea what the messages are? How to solve it?

Any easy to setup POP3 server available?

Question by:ccjong
    LVL 2

    Assisted Solution

    This usually happens when the MX pointer in the DNS system points back to itself.

    Please post the output of the following commands:

    cat /etc/hosts

    cat /etc/resolv.conf

    netstat -plutn

    Also try dig to spot DNS problems.

    shell>dig type=mx

    Chances are either your local network resolution, hostname, or DNS for mail are incorrect. In most cases where I've seen the MX loop issue, the person is running the DNS and MAIL on the same box.

    Let me know if this helps you,


    ~K Black
    Irvine, Ca.
    LVL 40

    Accepted Solution

    That error occurs when the mail server doesn't believe that it is the mail server for the domain, but it sees that the MX record does point to itself. This can be caused by incorrect network configuration where the hostname or the hosts file is incorrect or by failing to list all names the server is known by in /etc/mail/local-host-names.

    The hostname of the machine needs to be the FQDN of the server (e.g., in /etc/sysconfig/network ""). And the hosts file should contain:     localhost.localdomain localhost mail

    /etc/mail/localhost-names would then contain:


    Author Comment

    Thanks for the help.

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