We've heard a lot about whitelisting and blacklisting, but many are unfamiliar with the term "greylisting" and, to a lesser extent, "rate limiting." Greylisting and rate limiting are two additional but lesser used methods which some ISPs may employ to attempt to deal with spam and/or a sudden influx of bulk email.
We wanted to do a mid-year check-in to remind you to make sure that your emailing practices are staying in tip-top shape, and that your email marketing campaigns were minding their p's and q's to ensure maximum deliverability.
Users of mass email services such as Gmass, Woodpecker, Lemlist and others, that have been using Gmail's API to send bulk email that tricked recipients into thinking that they were receiving personal one-to-one emails, have been put on notice today by Google: "Applications that use multiple accounts to abuse Google policies, bypass Gmail account limitation, circumvent filters and spam, or otherwise subvert restrictions are prohibited from accessing Gmail API scopes."
One of the many things that we explain to people in our Email Deliverability Handbook is that while you must comply with the CAN-SPAM Act, you shouldn't say that you comply with the CAN-SPAM Act. This advice may seem counter-intuitive, however here's why.
You'd think that by now people would understand that spam complaints impact your deliverability, both to the inbox and, ultimately, even to the inbox provider themselves. Yet we regularly get questions and comments, both in the course of our business day, and in casual conversation, which make clear that there is something that people just aren't grokking, so here it is, put as plainly and clearly as we can put it: If you get too many spam complaints YOUR EMAIL IS GOING TO START GOING TO THE JUNK FOLDER and may eventually be blocked. Period.
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").
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?
Many email senders rage against the machine - the spam filtering machine, that is, and specifically spam filters for email. And it's easy to understand why: legitimate email getting caught and misidentified as spam, also known as false positives, can play all sorts of havoc for an email sender. But consider this: what would the email world look like if the email receivers (ISPs and inbox providers) didn't use spam filters?