Email marketers’ lives just got even tougher with the recent changes to the Windows Live Hotmail user experience, which enables users to better organise their inbox.

The changes include the addition of a trusted senders icon to prevent phishing; the ability to “sweep” or automatically file “grey/gray mail,” email that subscribers signed up for but no longer want; and the use of one-click and time-travelling filters, which remove messages that reach the inbox but are later discovered to be from senders with a poor reputation.

The good news is that email marketers can proactively ensure their emails continue to reach the inbox, in spite of the changes. Working to maintain a high email reputation score and keeping complaints to a minimum will certainly benefit all marketers, not just those with a large portion of Hotmail subscribers in their email databases.

In addition, it is just as important to pay attention to performance data and what that data says about the inactive portion of an email database. Marketers with a large segment of non-responsive subscribers will need to do some housekeeping to ensure all of their email campaigns continue to reach the inbox. That housekeeping comes in the form of a win-back campaign.

While some marketers may shudder at the thought of streamlining their email database, implementing a win-back strategy is actually a win-win scenario, despite what some recent industry articles have advised.

Sure, it may be easier to ignore the inactive segment and continue to mail to these subscribers because it doesn’t really cost anything and they may choose to respond at some point. This approach may provide some short-term gains in the form of additional opens, clicks and conversions, but it ignores the long-term damaging effects of mailing to an email database with a large non-responsive segment.

In other words, there is a very real cost to continuing to mail repeat non-responders. Marketers may be surprised to find that 40-70% of their address book may in fact be dormant. With some ISPs beginning to use engagement metrics as part of the reputation data that is used to filter mail, marketers who continue to mail subscribers that no longer interact with their messaging could see their emails getting sent into spam folders and possibly blocked at the ISP level.

Moreover, inactive subscribers have little economic benefit to the marketer, but are at risk for driving down the reputation metrics that we know are in heavy use today – including generating spam complaints and eventually turning into spam traps or dead addresses.  

The bottom line is that the deliverability of their entire database could be affected, preventing those subscribers who regularly open, read and click on their messaging from consistently receiving it.

As a result, implementing a win-back campaign is no longer simply a nice-to-have strategy, it’s now essential for the health of marketers’ entire email databases and it directly impacts on email deliverability, as well as response rates.

So, where to start? Below are four initial strategies to help map out a successful win-back plan:

  • Define the inactive segment. For example, for a publisher sending daily newsletters, is the inactive subscriber someone who hasn’t opened or clicked in one month? For a retailer sending weekly promotional mailings, is it someone who hasn’t purchased after six months? 

    For social networking sites, is it someone who hasn’t clicked on the links in transactional messages or updated their profile in one year? Defining this segment will help determine what percentage of recipients are inactive and the type of audience to reach out to with a win-back campaign.

  • Create a series of win-back mailings designed to grab the subscriber’s attention. Include an incentive to act, such as a coupon or free delivery offer. Consider other types of incentives, such as downloadable content, a survey or a contest. Whatever is sent, focus on making an impact.
  • Be sure to send win-back campaigns from separate IP addresses; it’s likely that some of the inactive portion consists of spam trap addresses. Inactive subscribers may also be more likely to complain, so using a separate IP will protect a brand’s existing reputation.
  • Get rid of the dead wood. Reach out to persistent non-responders with a last chance re-permission message. Once it’s determined who’s still interested and who isn’t, send a final message asking to re-permission these subscribers back on to the email database. Include a deadline to increase the urgency of the message. If the subscriber doesn’t click on the link or take a desired action, remove them from the database and stop messaging them.

Almost every email marketer likely has some Windows Live Hotmail addresses on their database; in some cases, those addresses will make up the majority of it. There’s more details on the Windows Live Hotmail changes in my colleague Tom Sather’s fascinating blog post.

Poor email reputations will result in marketers emails failing to reach millions of inboxes. With ISPs strengthening their defences against spam, the onus is on email marketers to protect their email reputation and differentiate their messaging and their practices from spammers. This includes being proactive about inactives: don’t fall foul to the silent, but deadly, non-responsive subscribers.