I went to mxtoolbox.com and this is what i got.
Looks good on our end. I even checked the blacklists and we look good...
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Browse All TopicsHello all,
I am encountering an email issue with one of our employees. It is when he sends an email to a company (lets call it xyz) He has tried multiple contacts in the company (we know they are accurate). However the emails bounce back immediately with the following error.
Any thoughts? I had our ISP change our pointer record so a reverse lookup is now the correct dns entry...
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This part of DNS Report from www.dnsstuff.com may highlight a problem:
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.
f3partners.com.s9b2
If someone is using Postini, the tools on dnsstuff.com are useless for confirming behaviour on outbound email, because they cannot test for that.
Note that the error above is for 75.144.198.237, whereas you have posted in a second message that you tested 75.144.198.235.
I do an nslookup on 75.144.198.235 I get the result you are expecting.
Therefore if your email is supposed to be going out on 235 then you need to check your NAT.
Simon.
Business Accounts
Answer for Membership
by: alanhardistyPosted on 2009-09-03 at 10:59:08ID: 25253153
I would try setting up an SMTP connector for this domain to send out via your ISP's smarthost (call them for the IP Address) and then test sednign again.
This is what they are asking you to do - so worth a try.
http://technet.microso ft.com/en- us/library /aa996625( EXCHG.65). aspx
Check your domain on www.mxtoolbox.com/diagnost ic.aspx to see if other errors are present on your domain / configuration.