Many email professionals use Microsoft's Exchange server to send out their emails from Campaign Enterprise or Email Marketing director. The number one complaint we get is usually that it is very slow even though they are on "a super fast system on a fast internet connection." By default, Exchange Server is not setup to be a mass email system. In fact, they have created many settings by default to stop email from being accepted at a rapid pace. Depending on your Exchange Server version, there are settings you can look at to stop this throttling. A prominent term used is "tarpitting." Now the subject of tarpitting mainly concerns a set of parameters you can set in your Exchange Server so that it will accept emails at a rapid pace. Because of all the version of Exchange Server out there, and with them trying to deal with the SPAM issue through time, there are different settings for each of these versions which we cannot cover, but hopefully this article will uncover a nagging problem you might be having. Now keep in mind, many Exchange Server administrators may not even know what you are talking about because it is a rare occurrence and they probably have not encounter it before, so you may have to prime the pump with some Google service on "Exchange Server SMTP slowness" and show them some of the settings they will have to deal with.
Relaying Through an SMTP Server
One of the most confusing terms regarding email marketing is relaying. Relaying is not a bad word, as some ISPs would lead you to believe; in fact, it is the only way to get emails from point "a" to point "b" while using an SMTP server. Like a baton in a relay race, an email is passed along from one mail server to another, with the goal of getting to the finish line without being dropped. At each transfer, the email is relayed from one server to the next until final delivery. Problems occur if the SMTP server to which the email is first submitted has relay options that are not configured correctly. There are generally two states an SMTP server is in concerning relaying: open relaying or closed relaying.
Open relaying is where all the problems start. It is actually the state of a server sitting out on the Internet to which anybody has access. Email servers that are configured to run wide-open are a major access point for spammers. As soon as an SMTP server is placed online, if it is not configured properly, it is hijacked. Back in the olden days, the default option was to allow anybody and everybody to send through a mail server. Eventually the default for new operating systems was to keep the relaying closed. Some SMTP servers remove the open relaying altogether to prevent accidentally making it open. With open relaying, the server is guaranteed to be used by someone else to send spam messages and cause the server to get blacklisted. Many mail agents check the server settings by sending a test email to see if the SMTP accepts it. If the test is accepted the recipient server may decide not to accept the email from that server, legitimate or not. Never, ever use open relaying.
One of the traditional methods spammers use is finding an SMTP server online without any restrictions in place and use it to send their emails. This can effectively hide their tracks and could cause potential problems for the legitimate server they confiscate. Several online organizations have taken it upon themselves to identify potential spammers and stop them from using other peoples open mail servers to send spam. The IP address of the server that appears to be open, is added to a database that is checked by subscribers and set to deny emails automatically. If this happens to a legitimate business, contact the database administrator to request that your company be removed from the list on the condition that the problem with the server be corrected.
Closed relaying, like open relaying, is merely a description of the state of the server and is not a setting found in the relaying options. Closed relaying means that some sort of authentication must occur before someone can send emails through the SMTP server. The best way is to list a computer's IP address, or a block of addresses can be added to the server in the relay settings section, which vary by product. Enabling these features restricts access to the SMTP server and thereby closes it to people who are not approved. Further restrictions include authenticating with a username and password, and blocking connection requests from all but an approved list of computers. Most mail servers are now closed to all traffic, until a computer is specifically added to the list, or can authenticate.