MIME-encoded images?


I have a client who wants his campaign mailed largely to public-sector organisations, where users' email clients are pretty locked down and by default they can't see images in HTML emails.

He has asked why we don't just use MIME-encoded images (rather than pathed remotely hosted images) as a way of getting through these restricted environments.

I'm not even sure CM allows images to be sent in this way, but I'm pretty sure that that's not the only reason we shouldn't go this way.

Does anyone have any thoughts about using/not using MIME-encoded images? Are the mails likely to be identified as spam, for example?


Dave Dave, 10 years ago

Hi Tamper, we actually did some embedded image testing recently. Turns out embedded images are still blocked by default in most of the major web-based email clients, including Hotmail, Yahoo! Mail and Gmail. Just like externally referenced images, they display by default if you're considered a safe sender by that recipient.

This, combined with the fact that embedding an image sees a big jump in the file size of the email (as all of the images are included inline instead of externally referenced) means it's something we won't look much further into.

As you mentioned, it would be interesting to see what kind of impact image embedding has in regards to spam filters too. Anyone out there had any experiences with this?

tamper, 10 years ago

Cheers for the quick response.

Meridian, 10 years ago

Hi, I'm new to CM, haven't test it on any live campaigns yet, but so far I have to say it looks very nice!

I understand your point on file size, on the other hand, I am sure the open rate for not web based clients would jump up significantly.

I am a little afraid that average user won't even know how to display images in the email client, or won't even notice there is something "wrong" (in terms of something is missing). Or am I too sceptic?

Have you guys done any testing on that? Something like what % of XYZ users understands that the "X" icon can be replaced by a nice looking image if they click "Show images/safe sender/..."?

This issue bothers me a little bit, because we want/need to send image rich emails (photos of travel locations), where without them being nicely displayed the overall feeling of the newsletter is somewhat poorer.


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