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I am running several websites on a Windows VPS that have "recommend this to a friend" type of emails. I get frequent bounces.

The provider allows us to configure reverse DNS records for all the domains that are hosted on the server, which I did recently. The changes have propagated. I am doing this through their administration panel and I am not sure what happens behind the scenes.

I am still getting these errors in the log:

2009-09-22 22:07:50 200.221.XX.XXX OutboundConnectionResponse SMTPSVC1 XXXXXXX - 25 - - 450+4.7.1+Client+host+rejected:+cannot+find+your+hostname,

Is this not related to reverse DNS issues? Or this just a notorious mail exchange ( How can I verity that our server is correctly configured?

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up vote 1 down vote accepted

You want to confirm that your backwards name matches your forward name.

You probably want to try this against a nameserver which is not your own:

$ dig @someone-elses-nameserver -x mail.ip.address

This will get you a name returned. Then make sure that name is resolvable:

$ dig @someone-elses-nameserver name.returned.from.previous.dig

...and that the result of that query is an IP address -- preferably the one you started with.

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Your forward and reverse records appear to be in order, but you do seem to be lacking an MX record. I'm not familiar enough with the SMTP service on Windows to say that's the issue.

You can be lazy and one-line David's suggestion:

dig +short -x `dig +short`
share|improve this answer is the mail exchange that rejects our emails. I confirmed that the domain that we use in the FROM adress in the "forward to a friend" emails resolves properly, and that the reverse lookup returns the domain. Still no idea why this particular exchange does not accept our emails. – cdonner Sep 23 '09 at 17:27
is the From address in question who your server actually claims to be when it's trying to deliver? If not, that is certainly a red flag to email server operators... – Greeblesnort Sep 23 '09 at 19:27

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