Reverse DNS FAILED

I am using SBS 2008 when checking domain health with MXTOOLBOX I get the below DNS error. Smtp Banner Check
The SMTP banner issued by your email server did not contain the hostname we resolved for your server’s IP address. Please can you help me resolve this?
AJ1978Asked:
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Alan HardistyCo-OwnerCommented:
Okay - so sounds like reverse DNS isn't set properly, which needs to be done by your ISP.

Please give them a call and ask them to change your REVERSE DNS record as you need it configured.
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Alan HardistyCo-OwnerCommented:
You will ALWAYS fail the Mxtoolbox reverse DNS check because you have Exchange 2007 or above (2007 in your case).

The test from MXTOOLBOX checks your RECEIVE connector NOT your SEND connector which is what REVERSE DNS should match, so you can ignore the result from the website.

As long as REVERSE DNS matches your SEND connector FQDN and that FQDN resolves publicly to your Public IP address, then you should be fine.

A quick nslookup test will confirm this:

nslookup mail.yourdomain.com

should return your public IP Address e.g., 123.123.123.123

Then

nslookup 123.123.123.123

Should return mail.yourdomain.com

If it does, then you are good to go - if not, you need to correct it so that it does resolve properly.

Alan
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AJ1978Author Commented:
Hi Alan - Thanks, the first NSlOOK up worked fine but NSLOOK up the IP didn't, please can you advise.
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