Email Delivery Tips from EmailReach

These are the three main hurdles to delivery

1. Your Email Reputation

2. Content Filters

3. Actual Inbox Delivery

Let's quickly review the basics of each of these to get you started.....

1.Your Email Reputation

“You’ve been blacklisted.” Words that strike fear into the heart of any email marketer.

What Does this Mean?

Basically your sending IP address has been listed by a popular blacklist as likely to send Spam and therefore they have listed your email address on their “blacklist.” Once this occurs mail administrators and individuals that use this list as an IP block list will not take receipt of your email, send it to a junk folder or delete it altogether.

Who Manages these Blacklists and why do they think I send Spam when we are fully Can Spam Compliant?

Spam like beauty is in the eye of the beholder. If an independent group thinks that your message has some “spammy” characteristics they may or may not add you to their list. A number of the blacklists select with an algorithm that is independent of human selection. The bottom line is selection can be arbitrary and every legitimate marketer should be aware of this potential delivery rate pitfall.

What are the main Blacklists?

There are hundreds of blacklists out there, however there are 10 or so that are used the most by mail administrators.

1. Open Relay Database

2. Spam and Open Relay Blocking System

3. Spam Prevention Early Warning System

4. Vipul’s Razor

5. Pyzor

6. Distributed Checksum Clearinghouse

7. Spamhaus

8. SpamCop Blocking List


10. SpamFire

Each of these uses a slightly different technology to identify spam; it’s a very useful way for diligent mail administrators to control incoming email.

What do I do If I think I am Blacklisted?

Once confirmed that you have been wrongly assigned as spam there are number of things you can do. We strongly recommend you working to understand what characteristic caused you to be listed, and working to remove this trait from your campaigns. Typical issues are incorrect mail administrator settings, using a non-dedicated deployment machine, sending large volumes of mail in short periods. Once this is corrected reach out to the blacklist and request to be whitelisted. This often is easier if a third party request on your behalf. Whitelisting takes time far better to avoid blacklists in the first place.

2. Content Filters

Probably the most misunderstood area of email delivery filters are the numerous filters that mail administrators and individuals use to review email content prior to delivery. Inexperienced email marketers think that by making sure they avoid a number of key trigger words and obey a few simple rules they are good to go. One example we hear all the time, "don't use the word free in the subject line". Unfortunately it's not that simple, the filters that are being used have underlying logic that looks way beyond the subject line when assessing a message.

Here is a shortlist of the main content filters
  • Norton AntiSpam
  • McAfee Spamkiller
  • Lyris MailShield
  • Spam Assassin
How do they work?

These filters work on a number of different levels all that look for suspicious, code or content that has high spam characteristics. Spam Assassin for example tests obvious spammer tricks, such as misspelling potentially offensive words and forging domains or dates. Other tests seem innocuous but could cost you, such as "g a p p y t e x t" (0.5 points), and the subject or body IN ALL CAPS (0.3 points).
Below is a sample list of 5 tests (the point values vary depending on how the end user configures Spam Assassin):
The subject line is all capital letters. Score: 0.459 to 1.049. The message date is 12 to 24 hours before the receive date: 0.881 to 1.247.
The domain in the sender line doesn't match the domain in the "received" line in the headers: 0.217 to 2.127.
The message has bad MIME encoding in the header: 2.255 to 3.100.
The message is 90 percent to 100 percent HTML: 0.113 to 0.587.

How to avoid Content filters?

There are a number of basic steps that we recommend to all email marketers before they even start to tweak specific content filter issues.
1) Correct all basic HTML coding errors. Make sure all your tags are correctly placed and are fully compliant.
2) Create a template that scores low and continue to use it. Use an HTML validator to create this template.
3) Learn to see your message as a content filter does, header, subject main body. Make sure each of these is correct. Message headers are in particular are commonly full of problematic elements including mime errors and date and time inconsistencies.
4) Test your content, fix and then retest. We recommend a score below 5 on Spam Assassin. If delivery is vital lower this threshold to 4.
5) Improving your email reputation score will raise your ability to pass these these tests.

3.Inbox Monitor

We’ve discussed your email reputation and content filtering; let’s spend some time looking at where the rubber hits the road for email delivery: the ISP inbox.

Let’s be very clear about this for consumer facing campaigns there are 4 major ISP’s that manage the majority of consumer inboxes.

  • MSN/Hotmail
  • Yahoo Mail
  • AIM Mail
  • Gmail
What Does this Mean?

Basically unless each of these mail platforms relays your message to the primary folder, your email campaign is far from optimized.

What Causes mail to be delivered to a bulk/spam Folder?

All of these ISP’s allow their users to report spam with a “report spam” button. The ISP uses this feedback to create a profile for your mail. If users are reporting your mail as spam you will run into problems. AOL recommends keeping spam complaints below 1-3 percent of traffic, depending on volume. This figure is unique to AOL's user base; it's too generous when applied as a general standard. Be at or below the range of one complaint per 6,000 to 8,000 messages, or 0.013 percent.

Minimize Complaints

Minimizing complaints always starts with practices used to collect e-mail addresses. It should be obvious by now sending unsolicited e-mail only gets you in trouble. Mailing lists with the lowest complaint rates are either confirmed opt-in or properly managed single opt-in. If you have a solid permission-based list but still find incoming complaints are higher than the optimal rate or are rising, consider the following:

  • Brand your subject lines. Mail systems with spam complaint buttons offer it at the inbox level. A recipient needs only to scan subject lines and decide which messages not to delete immediately. A subject line such as "Exciting offers for you, Bob!" will surely be marked as spam. Consider using your company or newsletter name in brackets at the beginning of your subject lines.
  • Consider including unsubscribe instructions at the top of your e-mail, in addition to the footer. Some users use the "report spam" button as an unsubscribe method and won't scroll through an entire message to find that link.
  • Include instructions for users to whitelist your domain. This prevents a user-based filter from mistaking your message for spam and either diverting it to the spam folder or prefixing "[SPAM]" to the subject of the message.
  • Provide a preference update page. Disclose how your organization will use a subscriber's e-mail addresses, and how often. Allow subscribers to select preferences on the opt-in form, and link from e-mail to a preference or profile update page.
  • Avoid spammy looking content. Try not to use garish, bold fonts; large, red letters, and the like. Avoid images with poor compression quality. A clean, readable design isn't as likely to be mistaken for spam.
  • Don't over e-mail. If recipients expect to receive a few informational e-mail messages each month from your company, don't suddenly start sending two or three each week.
  • Don't send unexpected e-mail. If subscribers opted in to receive your "Trends & Tips" newsletter, don't send them your hard-sell e-commerce messages, unless they clearly requested them.
  • Include opt-in information. If possible, add to your e-mail admin area information, such as the subscriber's e-mail address, date of opt-in, and how she potentially subscribed (product registration, white paper download form, sweepstakes entry, etc). With many subscribers receiving dozens of commercial e-mail messages daily, it's easy to forget signing up for your newsletter -- and then to file a complaint.