A follow-up on Marketing Sherpa’s webinar “Improve Email Deliverability: Tactics for Handling Complaints and Boosting Reputation"

Return Path and Marketing Sherpa joined forces to present a webinar on how to deal with complaints. The turnout and questions were great.  So great in fact, that we ran out of time to answer them all.  Along with Marketing Sherpa co-presenter Adam Sutton, we decided to answer the questions in a two part blog series.  Here’s the first.  Adam’s will be presented on the Marketing Sherpa blog on May 3rd.

Q:  Any opinions on using a “mailto” link unsub header vs a “https” type list unsub header?  – Alex Wolski

The list-unsubscribe header is an optional x-header in emails that can be added to provide additional methods for your subscribers to unsubscribe from your emails without them having to search in your footer.  Webmail providers all use this functionality differently.  For example, Hotmail will display an unsubscribe link within their interface if the list-unsubscribe header is present and the subscriber has you added to their trusted sender list, or if they are Return Path Certified.  Gmail uses it as a poor man’s feedback loop by allowing people who report spam to also unsubscribe if they choose to do so.

There are a couple of ways to implement this as Alex points out.  You can use a MAILTO link which will prompt an email to be sent to the address specified.  It would look something like:

List-Unsubscribe: <mailto:[email protected]>

The other way to do it is web based which is what most people include in the footers of their emails for people to unsubscribe.  I strongly recommend using a one-click unsubscribe for this method.  Otherwise, you’re making too complicated for users.  However, you could in theory send them to your preference center.  An example of this would look like:

List-Unsubscribe: <http://domain.net/unsub/?id=1234567>

So to answer Alex’s question, which is the best to use?  Both of them.  For example, Gmail only uses the MAILTO: feature, where Hotmail allows for both.  Yahoo, while not currently using it, had mentioned that they would be honoring both as well.  Keep yourself covered then by using both.  An example of this would look like:

List-Unsubscribe: <mailto:[email protected]>, <http://domain.net/unsub/?id=1234567>

Q:  Sometimes when sending out emails, you don’t know if the emails are undeliverable. What do you do in that circumstance? – Amanda West

If you’re afraid that your may have high unknown users on them, it’s still okay to mail them, just be sure that you remove them once you do have a bounce notification from them.  It’s possible that you may take a reputation hit as a result, but I wouldn’t worry because it will be short lived and your list quality will improve as you continue to mail and remove unknown users.

You should also have proper bounce rules in place in case your bounce processing system receives a code it’s never seen before.  We recommend disabling unknown users after one hard bounce.  It’s unlikely that it will ever turn into a valid address.  Some senders are a little more liberal and allow up to 5 hard bounces before an email is removed.  This is okay as long as you monitor your bounces and they don’t start to exceed 5%.  Soft bounces are a little different.  Some senders never disable them, and others disable them after 5 re-tries with no success.  They are meant to be transient in nature, so ISPs won’t penalize if your soft bounces are too high like they do hard bounces.

Any tips on how to get through a corporate spam filter when using an ESP? – Justin Frechette

Corporate spam filters are the most difficult to get through because they are decentralized, have custom filtering settings, are trained by system administrators and mail users, and have many more points of failure before reaching a users’ inbox.

Some of the more popular corporate spam filters are located at the gateway and include Barracuda, and McAfee.  You also have OEM filters to worry about like Brightmail, Cloudmark, and Postini.  If that isn’t enough, you  still have to worry about how Exchange will filter your mail.  If your emails make it that far, congratulations!  Now you just have to worry about desktop filters like Symantec and McAfee, as well email clients like Exchange.

I’d focus on two things for corporate filters though:  content and reputation.  These filters still rely heavily on content fingerprinting to determine if email is spam or not.  There are a lot of tools out there that will assess your content and give you a spam score or spam words, like Return Path’s Campaign Preview.  These filters also use reputation.  For example, Microsoft incorporates Smart Screen, it’s reputation filter, into not just Hotmail, but also Exchange and Outlook where they are looking at things like spam complaints, unknown users and spam traps.   Postini looks at content, but also will look at traffic shaping and unknown users to determine if your mail stream is a threat.  If your mail still isn’t getting through, you may have to reach out to the corporate entity you’re trying to get delivered to.  A lot of them have strict security policies in place to prevent phishing messages and malware from being delivered to their employees.

What are the recommended strategies for locating spam trap email addresses on our mailing list? – David Landers

Locating spam traps on your file can be difficult, and depending on the size of your list and how you source it, it could be even worse than looking for a needle in a haystack.  The best strategy is to prevent them from ever getting on your list in the first place.  Here are some methods to consider avoiding getting them on your list:

  • Avoid using any opt-out names, such as third party list acquisitions, append, etc.  They notoriously have list quality issues like spam traps.
  • Avoid Address Book uploads, or limit the amounts users can upload.  When’s the last time you’ve cleaned out your email address book?  Never?  Well neither have your subscribers and it is possible some inactive email addresses on their list have now been converted into spam traps.
  • Process bounces.  Since ISPs re-purpose email addresses into spam traps, not removing unknown users puts your file at risk for spam traps.
  • Monitor your welcome messages and spam trap reporting for spam trap hits and isolate segments if you see any new spam trap hits.

Here are a couple of methods to get rid of spam traps on your list if you’re feeling the pain now:

  • Have a reactivation strategy.  Define your inactives and then send a win-back campaign to try to win these inactives back into your program.  If they don’t respond, they’re either no longer interested in what you’re saying, or they’re a spam trap.  Re-permission or drop these.
  • Segment your data based on activity (email and website if you got it), send from different IP addresses (or segment by date and time if you have to), and then monitor your spam trap reporting for any hits.  You can do this as granular as your time and patience allows.

Additionally, if these two solutions feel like a lot of work (and they are), Return Path does have services that help save you time and cost associated with cleaning up and reactivating your lists.  Contact our professional services group to find out more.

Missed the webinar?  You can watch the replay.

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