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I'm using mutt & postfix on CentOS 6.2:

  • mutt-1.5.20-2.20091214hg736b6a.el6_1.1.x86_64
  • postfix-2.6.6-2.2.el6_1.x86_64

When I try to send mail to my company mailbox, I receive an error:

mutt -s "test" < /home/mail.txt 

Error from postfix:

<>: host[] said: 
555 Syntax error (in reply to MAIL FROM command)

Then I try to use service sendmail as SMTP server, but also failed:

   **----- The following addresses had permanent fatal errors -----
    (reason: 555 Syntax error)
   ----- Transcript of session follows -----
... while talking to
>>> MAIL From:<root@my_server> SIZE=667
<<< 555 Syntax error
554 5.0.0 Service unavailable**

I can make sure DNS is OK, and I set realname "root@myserver" in /etc/Muttrc

Any body can tell me why?

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2 Answers 2

Instead of using a local MUA,which may be configured in a myriad of ways, start by using telnet:

$telnet 25
>MAIL FROM: me@home
>RCPT TO: some@where.else
>Subject: Test

Then report what that says, and post the logs of the transaction.

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Your company mail server has annouced (after EHLO) that they support SMTP Service Extension for Message Size Declaration defined in RFC 1870. Because of it, postfix and mutt will add string SIZE=XXX in the end of MAIL FROM line.

>>> MAIL From:<root@my_server> SIZE=667

Unfortunately, your mail server complain with error because it seems they don't understand SIZE syntax.

<<< 555 Syntax error
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