Welcome to Internet Mail Server Networks.

553 host is missing reverse dns record.

If you have come to this site because of the url listed in a bounced email please read below to find out how to prevent future messages from being blocked by Internet Mail Server Networks mail systems.
If you are an administrator or postmaster and your users have sent you to this page please read about our requirements below.

We have just added a new restriction to the internetmailserver.net v2.0 services that denies inbound messages from systems lacking proper PTR RR records (Reverse DNS).

Lack of PTR RR records is highly suspect for a legitimate mail host following best practices for sending mails. As of today even the majority of reputable dial-up and broadband connections provide PTR RR records for their networks.

If you administer a mail server that does not have PTR RR records set for your mail server you will receive a 553 error message and warning that your reverse records could not be found. We will not white list senders of this requirement, senders should setup proper PTR RR records, or contact their upstream provider to do so for them if they do not have authority over their in-addr.arpa zone..