rDNS non-existent error

[supercoups]

I have a few emails in my IMS queue with the following error as to why they cannont be delivered:

[451 4.3.0 rDNS "[12.111.74.64]" non-exisitent]

I am assuming it is because the recipient's mail server is trying to do a reverse lookup on my mail server and it is failing. Can anyone tell me how to allow a rdns lookup on my mail server? I am running exchange 5.5

Thanks in advance,
Jim

 

[jonlake]

You will need to ask whoever is providing the DNS services for your internet IP (most likely your ISP) to add a PTR record.

Jon