Simple Mail Transfer Protocol: How to create an outgoing SMTP server

How much email traffic does your outgoing mail SMTP server handle regularly? Hundreds? Maybe even thousands?

Bulk mailing can help you keep in touch with the customers you have built up by sending them coupons and special deals, making it a crucial step.

The last thing you want to see is an ‘unable to send’ message. It is far from rare for a number of messages to fail when sending mail in bulk.

What kind of effect on you business will you experience if 10-10%, or even all of your messages, fail to be delivered? This is a major problem that you may have to face if anybody has decided to flag you as a spammer.

In the modern world upwards of 80% of all email sent is classified as spam. Almost everybody with an email address will do their best to evade spam. There are countless filters designed to block spam emails and email providers do their best to make it difficult for spam to get into your inbox. This can be detrimental to any authentic mail you may wish to send out.

Perhaps this is causing you some concern. This article is designed to help you overcome these spam filters, and set up your own outgoing SMTP server correctly. When you know what do to you can easily stop anti-spam filters being a problem.

Look at the following diagram: This diagram shows the steps your mail takes when it is being sent.

This assumes your opt-in list is legitimate and not classed as spam. If this is not the case then the following rules may not help at all.

There are five easy to follow rules. These rules are designed to check your mail before being sent. At it’s very basics an anti-spam filter is simply a way of ‘giving trust’ to mail. As the filter checks your mail and lowers the score of trust, the lower the score gets the less likely it becomes that anybody will ever see your mail, anybody except a junk mail inbox that is.

Anytime you plan on starting your own outgoing mail SMTP server or plan to begin sending bulk emails, you want to follow the following steps:

- Acquire your own Static IP address;

* Get reverse and forward DNS resolution set up

- Look at blacklists

- Construct an SPF; and

- Compose Domain Keys (this is not necessarily required)

You might not be familiar with all these technical terms, but it’s a lot easier than you think, as you’ll learn in the steps below.

Acquire a static IP

The majority of regular Internet providers fail to give you this just for being a customer. Typically, a floating (dynamic) IP address is assigned, which changes each time you connect to the Internet. Keeping track of the address is like trying to hit a moving target. This makes the majority of email servers reject any bulk emails originating from a dynamic IP. Therefore, your first step is to contact your Internet provider and request a static IP address.

Forward & Reverse DNS Resolution

It is also required that your local outgoing mail SMTP server is configured with forward & reverse DNS resolution. DNS resolution happens anytime a client asks a name server to locate the IP address of the person it desires to connect with. Anytime the name server in a local domain is unable to answer a client’s request, the parent server is asked to locate a server that is able to.

They work together to make a type of authentication which a true relationship between the owner of a domain name and the owner of an IP address belonging to the email SMTP server. Having this validation will increase your trust score by a lot.

It provides yet another way you can be found using your domain name should you begin to send spam. Typically, spammers and phishers do not want others to know there real name, so they fail to follow this rule. Instead, they utilize stolen or hijacked domains and IP addresses. All provider require a type of ID, like a credit card, in order to register a domain.

A and PTR records are the processes that allow forward & reverse DNS resolutions to happen. These DNS records are important, so be sure to add them; getting DNS lookups require these. Your unobstructed Internet work will depend on this. This can be done by requesting it from your domain registrar or provider. With this accomplished, spam filters will start to trust you more.

You need to understand that just because you set an “A record” of your domain name in your DNS, your Internet provider may not have automatically configured a PTR record for you. Therefore, you want to check with them to make sure they did this, because there are times that they complete this task and other times that they fail to do it.

Look at blacklists

Using a DNS query you will be able to see DNS blacklists (also known as DNS block-lists. These consist of a list of IP addresses which are stored in a different database. The blacklists are used to prohibit IP addresses that send spam from doing so. All mail servers check if the IP-address of the client that sent the message is on the blacklist. If it is, the message is marked as spam and prevented from being delivered.

If this is happening to you, you can find out why the emails are failing to get delivered. There are even manual ways of getting your IP address off the list, enabling you to try sending emails again.

Configuring SPF

You may not know what SPF is. Unlike DNS, SPF is not required but is in fact useful. SPF validates whether or not a host is able to send emails for a particular domain. SPF allows filters to decide if your IP allows you to send messages for certain domains. If your IP is different than that designated then it will mark your mail as spam or delete it altogether.

If you’re on the SPF record, servers can verify that your messages are legitimate. Check out Openspf.org, which can tell you everything you need to know about SPF and how you can use it to your full advantage. Get your SPF set up through your domain registrar or provider. Their configuration panel might have wizards that can help you. You can get automatic SPF setup for your emails.

Domain Keys (optional)

If you feel you need additional help, you can use this lesser known standard for inspection. It’s debatable whether or not it can help you. Not very many providers check it anyway.

With Domain Keys, email senders can be correctly identified. It’s not unlike SPF in that it verifies that a legitimate person is sending the email through including cryptography in the email.

Although this does not filter spam independently, it can help with increasing trust for certain filters and providers. With the correct domain keys it is expected filters will not mark your mail as spam.

That is all you need to know. By following these few rules you will be able to act openly while communicating using the Internet.

As you make an outgoing mail SMTP server of your very own, you can use these steps to your advantage to make spam filters less of a problem, and to make you more trusted within them.

Those five simple tips will go a long way to avoiding problems.

Learn more about Smtp2Go. Stop by Tyson Griffen’s site where you can find out all about Smtp2Go Review and what it can do for you.