Problem sending email

	Having a problem sending email?

•	Some companies or individuals who have their own mail server operating on a dynamic IP address frequently encounter a peculiar situation. They find that their email messages are delivered to some recipients but refused by the email servers of other recipients. One of the reasons that this occurs is that some organizations, AOL and others, try to protect their subscribers from receiving SPAM. One way they try to accomplish this is to verify that the sender is legitimate by performing a "reverse DNS lookup." Here's how that works.

•	When you send an email message and your mail server completes the connection with the receiving server it tells the receiving server your current IP address. This is part of the SMTP protocol (Simple Mail Transfer Protocol). If you have a dynamic IP address the mail servers at some ISPs refuse the email immediately. If your email is not refused, the receiving server performs a "reverse DNS lookup" on your IP address to determine the domain name associated with your address. (Commonly a DNS lookup starts with the domain name and then finds the associated IP address. The "reverse DNS lookup" starts with the IP address and finds the domain name.) It finds that the domain name associated with that IP address is the domain name of your ISP. (Remember, your IP address is owned by your ISP and “leased” to you.)

•	Next your server sends a "HELO" message to the receiving server and that message contains your domain name. The receiving server compares the domain name it discovered through performing the "reverse lookup" with the domain name your server sent. If these two domain names are not the same, the receiving server assumes that the email message is SPAM and rejects it. Not all receiving servers perform the "reverse lookup" so your email may be rejected in some cases but not all cases.

•	To solve this problem you should send your email out through our Outbound Mail Relay Service. Using this service, your email server relays outbound messages through one of our servers. The email is acceptable to the receiving email server because the domain matches a static IP address. But this all occurs “behind the scenes” and the reader of the email still sees that the message is from YOU at YOURDOMAIN.

•	In addition, some ISPs block port 25, the traditional email port, to prevent you from running your own email server. The OMR Service can relay outbound email to a different port, circumventing the block. Our OMR Service is an inexpensive and easy-to-use solution to an otherwise troublesome problem. Click here for more information about the OMR Service.