There's an issue I've been pondering for the past few months regarding "Embedded images" vs "Remote images".
I'm sure everyone is aware of the old remote image hack (often a 1px transparent gif image), where an image is linked to a script on the server, so for example, an embedded image in an email might be something like (conceptually):
Code: Select all
<img src="http://server.com/log_email_opened_successfully.php?recipient_email=thisperson@blah.com" alt="" />
However, this method is as old as ths hills, and many say it's long forgotten as it's immediately recognisable by spam filters etc as an unethical/spam technique, and will probably get listed as spam or maybe even blacklisted?
There is some discussion on the topic in this thread: return-receipt 1pxl img hack
But on thinking about it, I realised that Embedded images these days ARE HIDDEN by default in all modern email clients. That is to say, when opening an email with embedded images, the email client will show a msg of something like "messages have been hidden for your security, click here to display".
So if that's the case that email clients are hiding embedded images. Then is there any real reason to NOT use remote images any more? If clients are going to hide BOTH techniques, then I'm wondering, why NOT use remote!?
I guess the question comes down to, what are the consequences of using the remote image tracking technique? Is it ONLY trapped by email clients? Or is it marked as spam on servers? Will it cause domain to be blacklisted? etc? Anyone have any useful info on this topic?
Cheers!
EoN