Getting Email Delivered - the ISIPP SuretyMail Blog

Anybody who sends email has seen them, in one form or another - those SMTP error codes, often returned in bounced email, such as “550 Requested action not taken: mailbox unavailable” or “550 5 2 1 mail from refused spam site.” These are often in response to SMTP commands that have ‘gone wrong’ between your email server that sent the email, and the receiving email server that is unable to deliver it (or refuses to deliver it) for some reason. But what exactly do they mean? And why should you care? (’SMTP’ stands for Simple Mail Transfer Protocol.) First, here is a list of SMTP messages and error messages, and what each message is supposed to say and mean

Today I want to let you know about another free resource that we offer to the general public along with our customers: a free tool that allows you to determine whether your reverse DNS (rDNS) is set up properly.

Did you know that setting up an automated “I’m out of the office” vacation auto responder message can hurt your email deliverability? In fact, there are a few different ways that those automatic vacation reply messages can hurt your email delivery, and for that reason, we advise you not to use them at all or, if you must, to use them very carefully.

Back when I co-founded Habeas, we came up with the at-that-time novel idea to have our accredited senders insert special headers in their outbound email. Those headers were a signal to the receiving email servers that our senders had been accredited and the email was promised to be “not spam.”

We’ve very excited to announce our free (yes, free) email deliverability toolbar for both Firefox and Internet Explorer! With this toolbar you can instantly access many of our free email deliverability assistance resource from anywhere on the Internet! Do an IP address lookup, check reverse DNS (rDNS), check various blacklists, and more!

Often the way that you find out that a user’s email address is no longer valid is that you get a bounce back (”user not found”). But sometimes a user will switch email addresses, and they will actually try to notify you. What do you do then?

What if I told you that there is a way that you can get your email into the inbox 100% of the time? And what if I told you that it was guaranteed?

We’ve talked in the past about how important it is to be sure that your email renders well in many different email clients and devices, and also generally to be sure that your email is easy to read on mobile devices. But have you ever wondered what the majority of your users are using to read their email?

We’re always thinking about ways that we can boost our customers’ deliverability and email reptutation to previously unheard of heights. And, as we’ve mentioned before, open rates are becoming increasingly important. That is because ISPs look at your open rates to see if people are really interested in receiving and reading your email. So I got to thinking about things that can artificially supress your open rates.

Last week we talked about how if your email is not “mobile friendly”, that is, if it doesn’t render well on mobile devices, your email will not bring you the results for which you are hoping. And because once someone reads your email on their mobile device, they aren’t as likely to read it on their computer, this is very important. Remember that open and click-through rates can directly affect your deliverability.

I’m sure that you know that more and more people are reading email on the go (I, for example, read a large percentage of my email on my Sidekick, many others read email on their Blackberrys). In fact last year Marketing Sherpa determined that 64% of key decision makers are reading email on their mobile devices. Reading your email on their mobile devices. Have you ever stopped to think about what that means in terms of your email deliverability?

Challenge response systems have been around long enough now that pretty much everybody has an opinion on them. The end users who use challenge response systems seem to love them. But legitimate email senders often never respond to challenges, and so the end users are actually missing out on a lot of wanted email.

A common complaint that we hear, particularly from email senders who are signed up for feedback loops from ISPs, is “why won’t the ISPs let us know who is complaining and clicking “this is spam” on our email, so that we can unsubscribe them?” There are a couple of reasons for that.

Many email senders rage against the machine - the spam filtering machine, that is. And it’s easy to understand why: legitimate email getting caught and misidentified as spam - what we call “false positives” - is a big problem. But, consider this: what would the email world look like without spam filters?

We’ve talked in the past about why address book importing is just not ok. But in addition to the fact that it trains people to enter their passwords at third-party sites, and to the fact that when you send out all those invitations it makes you look like a spammer, there’s another big reason to not do address book importing.

Three things happened within the last 24 hours which lead me to feel that today we need to talk about email personalization.

One of the most frustrating things for commercial and volume email senders is that different ISPs have different standards for what they require in order to ensure that your email gets delivered. On top of that, many ISPs don’t seem to adhere to the agreed industry standards in terms of how their receiving mail servers interact with the sending mail servers - for example five different ISPs may use five different SMTP error codes when they bounce an email because the email address doesn’t exist, even though people believe there to be one generally accepted code for that situation (along the lines of “550 user unknown”).

I’m sorry that we didn’t post a new article yesterday but, you see, my hard drive crashed. And so today I want to talk to you about the importance of regular backups, and to share with you my own backup set-up which, I’m happy to say, was very effective.

What do a spammer and two legitimate email marketers have in common? They all had their brand new IP addresses blocked as soon as they started using them. And you can too. Here’s how.

You know, sometimes it’s the silliest, most boneheaded things which trip us up. This is true for your email too. See if you can spot the mistakes in this email (this is a genuine, unretouched email, other than our changing the name of the service to “Geegaw” in order to protect the hapless).

Once upon a time somebody - somewhere - somehow decided that it would be good idea to send email to their mailing lists using an email address in their “From:” field that didn’t really exist. But sending email “from” an email address that doesn’t really exist is a spectacularly bad idea. In fact, it may even qualify as the Epic Fail of “from” email address ideas.

Most legitimate mail senders know to process bounce messages. This means that if they get what is called a “hard bounce” for an email address on their list (meaning that the bounce tells them that the email address simply doesn’t exist), they remove the email address from their list permanently. But more and more ISPs are inserting the bounce message right into your mail log, right at the time of the SMTP transaction, instead. If you don’t check your mail logs regularly, you’ll never see the bounce.

Just mention the term ‘DNS’, and many email senders’ eyes glaze over; say “rDNS” and a look of panic may replace the glaze. Yet, not only are these not complicated concepts, but having rDNS set up is critical to having consistent, good email delivery. To test whether you have rDNS set up, you can use our handy test rDNS tool.