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[cuantica]

Hello, I have a message in queue for about 24 hours and checking the delivery log I found this.

LOG: MAIN
cwd=/usr/local/cpanel/whostmgr/docroot 4 args: exim -v -M 1INUw5-0007VU-DZ
delivering 1INUw5-0007VU-DZ
Connecting to mx.uol.xxx.br [xxx.xxx.com.br]:25 ... connected
SMTP<< 220 starfury20.xxx.com.br ESMTP
SMTP>> EHLO svr01.xx***********
SMTP<< 250-starfury20.xxx.com.br
250-PIPELINING
250-SIZE 20971520
250-VRFY
250-ETRN
250 8BITMIME
SMTP>> MAIL FROM: SIZE=3111
SMTP>> RCPT TO:
SMTP>> DATA
SMTP<< 250 Ok
SMTP<< 450 Client host rejected: cannot find your hostname, [74.86.12.2]
SMTP<< 554 Error: no valid recipients
SMTP>> QUIT

I have checked dnsreport for this domain and found this

WARNING: One or more of your mailservers is claiming to be a host other than what it really is (the SMTP greeting should be a 3-digit code, followed by a space or a dash, then the host name). If your mailserver sends out E-mail using this domain in its EHLO or HELO, your E-mail might get blocked by anti-spam software. This is also a technical violation of RFC821 4.3 (and RFC2821 4.3.1). Note that the hostname given in the SMTP greeting should have an A record pointing back to the same server. Note that this one test may use a cached DNS record.

***********.co claims to be host svr01.xx*********** [but that host is at 74.xx.xx.2 (may be cached), not 74.xx.xxx.13]. <br />

What should i do to correct this error? btw, I host about 100 sites on this server.

[david510]

SMTP<< 450 Client host rejected: cannot find your hostname, [74.86.12.2]

The reverse dns for 74.86.12.2 is set as following.

74.86.12.2 PTR record: litiumweb.com.

Try setting the reverse dns as full server hostname. eg, host1.litiumweb.com

[Cristi4n]

It's ok, ignore that. Also ignore dnsreport on that, you need to check if the primary ip address on the server is ok, not the domain address because by default e-mail is getting out through the primary ip. If indeed your site's ip address is the primary address of the server then you need to change the HELO in exim to the PTR of the ip. If you do not have one, just ask the guys were the server is to set a PTR for that ip.

[Patrick]

The problem appears to be that the sender has not specified a valid recipient.

SMTP>> MAIL FROM: SIZE=3111
SMTP>> RCPT TO:
SMTP>> DATA
SMTP<< 250 Ok
SMTP<< 450 Client host rejected: cannot find your hostname, [74.86.12.2]
SMTP<< 554 Error: no valid recipients
SMTP>> QUIT

Notice the parts highlighted in bold...