#5.5.0 smtp;550-Verification failed

We are using exchange 2003 with google postini mail security for incoming mails. We have postini mail servers in the MX record with higher prefrence. For out going mails we are using our own smtp server. all is working well except some domains are not accepting mails from our domain, message bounced back with "#5.5.0 smtp;550-Verification failed " error. Our domain name is mabanisteel.com and the mail server host is mail.mabanisteel.com.

Please help as this issue becomes very critical for us.

Thanks in advance

Who is Participating?
SurajConnect With a Mentor Commented:
This is not your exchange issue. its the remote domain's issue.
This issue is usually caused when you have a POSTFIX or Exim server on the other end. They have a known compatibility issue as explained by some here. The best way to get this resolved is to speak to the other admin to make the adjustments in Postfix/Exim. It is not an issue with Exchange Server

Also check it:

What many sites will do is attempt to call back to the server that is sending the message to verify that it is valid. The idea being that a BOT would not respond. If you have restricted the server down to accept email from Postini (Which is what they tell you to do) then this test would fail.

Your best option would be to route email out through the same service that they come in, then these tests would be a success.

Is this happening for one domain or all the external domains?
did u try to telnet to that domain on port 25?
whats the result?
is it showing you banner or is it dropping the connection?
whats your exchange server?  2003 or 2007?
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sorry for the last question...
since its  2003 ,, go to properties of default smtp virtual server
and enable the logging... select.. NCSA log format..
restart the smtp service...
try doing the telnet again

i am waiting for your response....
FaisalYameenAuthor Commented:
Thanks Simon for your reply, we will try this option and will let you know the results.


FaisalYameenAuthor Commented:
It is happening with some domains only, OK I have enable the logging with NCSA format please see the telnet results after that

220-boat.securenet-server.net ESMTP Exim 4.69 #1 Sat, 16 May 2009 15:11:54 -0400

220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.
helo gulfconsultae.com
250 boat.securenet-server.net Hello mail.mabanisteel.com []
mail from:faisal.yameen@mabanisteel.com
250 OK
rcpt to:supervision@gulfconsultae.com
550-Verification failed for <faisal.yameen@mabanisteel.com>
550-Previous (cached) callout verification failure
550 Sender verify failed

FaisalYameenAuthor Commented:
Thanks X-Sam I am contacting the admin on other side hope this will be resolved then.

Faisal Yameen
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