March 11, 2010
Best Practice

9 Best Practices for Protecting Your Email Reputation

SUMMARY: Maintaining a good email reputation is a never-ending challenge. Between the shifting policies of ISPs and the changing makeup of your subscriber lists, last year’s good reputation could always be dinged this year.

Don’t fret: We’re highlighting nine best practices to help protect your email reputation. These proactive steps help you focus on the elements of reputation that you can control, even as external forces continually change.
A good sender reputation is one of the best assets an email marketer has to ensure messages are delivered. But because each ISP gauges reputation differently, and the factors that influence assessment can change, you must be vigilant to protect that asset.

To help, we’ve compiled this list of nine best practices to protect your email reputation, adapted from the deliverability chapter of MarketingSherpa’s Best Practices in Email Marketing Handbook.

Adopt these practices and make reputation monitoring an ongoing component of your email marketing processes to give your email campaigns the best chance of reaching their intended recipients:

1. Avoid changing your IP address

Spammers are famous for switching IP addresses. However, as a permission emailer, you may need a new IP address for a good reason (new server, dedicated server for testing, etc).

In this case, just be aware that IP addresses with no volume history are subject to higher levels of traffic shaping (controlling the volume of transmission) and mission throttling (i.e. limited or irregular email transmission) as well as more stringent reputation thresholds.

2. Monitor your reputation data

As part of your ongoing marketing metrics, develop exception reporting, so that you’ll be able to immediately act on unusually high or low statistics.

- Complaint rates

How frequently do recipients identify your email as spam? You can compile this rate from ISP feedback loop data.

- Hard bounce rate

This is the percentage of your file that consists of bad email addresses. Your ESP will provide you with your bounce rate as well as hard v. soft bounce data.

- Spam trap hits

The Web is "seeded" with fake email addresses that have been planted specifically to lure spammers (who collate the fake email addresses into email lists). Also, sometimes "dead" email addresses (email addresses that were once active, but have not been in use for 6-12 months) are repurposed into "honeypots" by ISPs. Those emails are planted on websites to attract spammers who harvest the web for email addresses.

Because sending email to spam traps is such an obvious non opt-in practice, most third party services have very low tolerance for spam traps.

3. Do limited test runs

Before making any significant changes to your email program -- particularly in the type of content or the frequency of your sends -- test the changes with a small portion of your list and measure your complaint rate. If the new email boosts your complaint rate, you’ll need to rethink your strategy. Even something as simple as changing the "From" address can cause a spike in feedback loop complaints.

4. Quarantine new opt-ins or risky test email campaigns

You should isolate email sent to newly opted-in addresses via a separate server until you can determine the email list quality. This practice is common for emailers who have obtained opt-in names via sweepstakes, co-registration, a partnered opt-in program or any other opt-in sources that might not be as committed to getting email from you as people who come directly to your website to opt-in.

Other types of promotions that some marketers quarantine by using a separate IP include:
o Testing small quantities of potentially complaint-generating campaigns
o Re-qualifying old portions of your list
o "Mystery" lists -- lists of dubious origin

If the email transmissions from the lists yield higher than average hard bounce rates, feedback loop complaint rates, or spam trap hits (unlikely for an opt-in campaign), don’t just add those names to your "good" server. Try to re-permission the names, conduct list cleaning or in a worst case scenario, dump the names.

Keep in mind that you also have to manage the output from your "quarantined" IP address. You’ll need to use the IP address on a regular basis, and dole out small quantities (5,000 names or less) for transmission. If you try to transmit from a new or relatively dormant IP, and/or attempt to transmit a large quantity of email names quickly, an ISP may stop or throttle that campaign based on either of those factors.

Also, be ready to take immediate action on any bounces, complaints, etc. originating from that IP address; because you’re using it for more risky lists, you need to be extra vigilant about the list housekeeping associated with it.

(Note: ISPs are beginning to shift to domain-based reputation scoring, which assigns the same reputation to all of an organization's email, regardless of the IP address used. This shift makes it especially important to protect the reputation of ALL your IP addresses, including ones which you use for quarantining new opt-ins.)

5. Process unsubscribes quickly

Remove opt-outs from your list before the next email send to minimize complaints. As part of your email campaign audit process, test your unsubscribe process before each send to make sure that it still works.

6. Process CAN-SPAM opt-ins quickly

While CAN-SPAM regulations give you 10 business days from the date of opt-out request to add a name to your "Do Not Email" (DNE) list, it’s best to add the name prior to any subsequent commercial email sends.

7. Remove feedback loop complaints

Once you’ve signed up for ISP feedback loops, which inform senders of spam complaints by email recipients, remove the complainers from your list before your next email send to prevent any additional complaints.

8. Manage and remove hard bounces

Remove those addresses that could not be delivered because the recipient is invalid, i.e. hard bounces/unknown users. Remove hard bounces from your list before your next send. You can attempt to rescue those addresses using techniques such as a direct mail offering an incentive to opt-in again, website alerts for registered users, or telemarketing.

Certain ISPs have a low tolerance for repeat sending of soft bounces. Remove those soft bounces from your list based on each ISP’s guidelines.

9. Manage your email volume

ISPs monitor the email volume sent by IP address. Either large spikes in volume, or small, intermittent volume, are causes for possible blocking or delayed delivery by an ISP.

If your volume goes up and you don’t notice, it could be due to a spammer spoofing you, or you may have a compromised server. If you proactively and knowingly increase your mail volume, you are likely to generate more hard bounces, more complaints, and thus, more scrutiny from an ISP.

Be sure to understand your emailing demographic, as an increase in complaints, hard bounces, etc. can potentially cause negative results in your deliverability.

Conversely, if you use an IP address intermittently, that raises suspicion as well. Email marketing experts have advised sending mail from a server a minimum of once per month.

Useful links related to this article

Receive hands-on email training at MarketingSherpa’s Email Essentials Workshops, coming to 10 cities beginning in March:

MarketingSherpa’s "Best Practices in Email Marketing Handbook":

Check Your Email Reputation to Improve Deliverability with Easy, No-Cost Tools

Deliverability Cheat Sheet - 27 Action Points to Fix Your Email Reputation Now:

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