How Yahoo! Mail's Image Caching Impacts Email Marketers

Posted by Rowland Marsh on 11/04/18 16:35
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How yahoo mail image caching affects email marketing

In a move that echoes Gmail's introduction of image caching back in 2013, Yahoo! has recently changed how it handles images in emails, caching them and serving them via their proxy servers. What does this update mean for email marketers?

Here we discuss Yahoo! Mail's image caching update, outlining the key considerations for email marketers and impact on campaign tracking and dynamic content targeting.

What is email image caching?

When images are cached in emails, they are downloaded from the original server and stored on a proxy server. When recipients view these cached images, they will load from the proxy server.

What does this mean for the sender? The images are rerouted, meaning that any associated image tracking is affected.

Why are images so important for tracking purposes? Well, email tracking pixels (which are images) rely on images to load, in order to provide email marketers with insights about open rates and other engagements, which are not only used to judge the success of campaigns but to trigger automated workflows linked to certain engagements and actions by subscribers and customers.

How does image caching affect email marketers?

Image caching impacts email marketers evaluating their campaign engagement and it can also skew dynamic content integrated with email campaigns, such as geolocation.  

When images in emails are downloaded, ESPs add a tracking pixel which counts the image loading as an open. Accurate tracking of opens, requires images to be downloaded each time recipients open an email.

Yahoo! Mail's image caching change also limits the ability for marketers to differentiate between email opens on desktop versus mobile, whilst the tracking pixel can no longer determine the length of email engagements for Yahoo! users.

As tracking and retargeting are crucial these days for retailers and email marketers, this is a big blow!

What's the impact on dynamic content?

If your brand uses dynamic content in emails, such as geolocation, Yahoo! Mail's update will impact the scope of your personalisation strategy, in terms of tailoring content to subscribers according to their location!

If you're sending targeted emails based on geolocation insights from image-related email open tracking, you could run into trouble. Your recipients' location could be shown as Yahoo!'s proxy server location, skewing your live content targeting. Therefore you may need to segment your Yahoo! Mail users or remove them any email campaigns using geolocation targeting. 

Thoughts of Enchant CEO, Philip Storey

Our Founder and CEO, Philip Storey had his say on Yahoo! Mail's update:

"This move from Yahoo! Mail highlights the need for marketers to keep abreast of changes from inbox providers because if you’re not aware of them, they can really catch you out!" 

Philip is one of the leading email marketing experts in the UK and he thinks Yahoo! Mail's update demonstrates why marketers must take a big picture view on measuring email marketing success. He continued:

"It also exposes the problems that we face as email marketers. Some of the metrics we continue to monitor are becoming less relevant. Open rate and click rate are still useful indicators of the effectiveness of email marketing campaigns, but they're not the only metrics to measure success against."

Wrapping up

It's important to be aware of the impact image caching will cause your analytics. Consider how to respond to this update in your email strategy and campaign targeting, especially campaigns using dynamic content. One positive is that Yahoo! Mail's image caching is only possible when subscribers are using an "yahoo.com" ID in Yahoo!'s mobile app or if logging into their webmail. Every cloud!

Are you ready to take a leap with email marketing this year and supercharge your performance? Enchant is offering retailers the change to get a free email marketing audit and roadmap. Apply for an email audit from our experts now!

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Enchant is a leading UK digital marketing agency, based in London. We offer a range of email marketing services and consulting for paid social advertisingCRM and inbound marketing. If you want to speak to an email marketing consultant, get in touch and see how we could help your brand create a big impact with effective customer-centric strategies!


Topics: Analytics, Email Marketing, Geotargeting, news, Personalisation, Retargeting, Segmentation, subscribers, targeted content, Targeting, email marketing performance, email strategy, email marketing trends, reports, email campaigns, Yahoo

Rowland Marsh

Written by Rowland Marsh

Rowland is the Marketing Manager at Enchant Agency. He is a writer, content marketer and former film reviewer. Rowland studied Literature and Philosophy at UEA and has a background in promotions, marcomms and print media.

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