End of an era at ExchangeDefender

Dear Customers and Partners,

I have just signed off on an implementation that in my mind is long overdue. For years ExchangeDefender processed messages from senders that did not have legitimate reverse DNS entries for their mail servers. As a major supporter of small business and a small business ourselves, we understand that at times it is difficult to appropriate enough funds to properly manage a complex IT infrastructure. As such, we have accepted messages from hosts that do not have valid PTR/reverse DNS because we are aware of how many small businesses rely on the unreliable and poorly configured appliances that generate real business email. Everything from copiers down to portable scanners now generates email of some sort, not to mention the many web sites and services.

However, dealing with this problem over the past year has become impossible to sustain. The amount of worms and botnets launched from dialup, dynamic and even missing DNS has been on an exponential rise and we continue to receive a bulk of our mail from mail servers that would not be accepted as a relay anywhere else. While we want to do whatever we can to assure email delivery, it is simply not feasible to ignore the RFCs anymore.

So, starting today, ExchangeDefender will require a valid DNS entry before accepting your messages. The mail will never be rejected but we will defer accepting it until you (or your IT consultant or your ISP) provide a valid PTR record / reverse DNS for your mail server. Should a message come in from a server that does not have valid reverse DNS you will get the following error: 

4.7.1 Access temporarily denied. ExchangeDefender requires you to have valid reverse DNS PTR record in order to send mail from [IP]

This is a hard-coded network-wide setting that does not allow for any exceptions. The sender will be notified immediately and will have a chance to setup a PTR record and allow us to accept their mail. For help with how to setup and manage DNS please have the remote sender contact their ISP.

This move will reduce the amount of SPAM you have to review each day and will reduce the number of worms and annoying SPAM messages you have been seeing over the past year or so.

I again want to stress that we did not come to this decision lightly but based on the statistical breakdown of where most of the threats were emerging we had no choice but to defer connections from hosts that do not comply with the basic standards that govern the way mail is sent around the Internet.

As always, thank you for your business and trusting us to keep your mailbox clean.

Sincerely,

Vlad Mazek, CEO, Own Web Now Corp.