Hello guys, I use Virtualmin. I have a Postfix problem (I think). Mails go out fine to most domains. However in the last week I have seen my customers complain that mails sent to people at two domains are bouncing. See below for the bounce message.
I have a PTR for my domain. I also have an SPF for my domain.
I have searched world-wide 
for an answer but no use.
Any help is much appreciated and you guys have already helped me in the past and for that thank you.
This is the mail system at host web2.manthrasolutions.com.
I’m sorry to have to inform you that your message could not be delivered to one or more recipients. It’s attached below.
For further assistance, please send mail to
If you do so, please include this problem report. You can delete your own text from the attached returned message.
The mail system
host smtp.equifax.com[216.46.96.105] said: 554 Transaction Failed Spam Message not queued. (in reply to end of DATA command) Reporting-MTA: dns; web2.manthrasolutions.com X-Postfix-Queue-ID: 17CAB6F0202 X-Postfix-Sender: rfc822; xxxxx@manthrasolutions.com Arrival-Date: Mon, 26 Mar 2012 14:36:21 -0400 (EDT)
Final-Recipient: rfc822; xxxx@equifax.com Original-Recipient: rfc822;xxxx@equifax.com Action: failed Status: 5.0.0 Remote-MTA: dns; smtp.equifax.com Diagnostic-Code: smtp; 554 Transaction Failed Spam Message not queued.
From: xxxx R Subject: Re: Test mail Date: March 26, 2012 2:35:47 PM EDT To: xxxx xxx Cc: xxxx@tcs.com
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