Tech Tips: Be Careful Forwarding Mailing List Messages

Here's a simple tech tip for you.

You're signed up to some mailing list. It could be for special offers from a business you shop at. It could be a newsletter for a charity. It could be just about anything. In comes something that you think is particularly helpful. You think "I'll forward this to my friends".

Just pause before you do so.

All (well, almost all - I'm sure there are exceptions) mailing list software will rewrite any hyperlinks within the email.

"Say, what?", you say. This: Within the email, there may be click able links. They could be to the website of the business or charity who is sending out the mailing. They could be to a news story that is being discussed within the email. They could be just about anything.

The author writes the email, and includes those links. The mailing list software gets hold of their message, and prepares to send it out to all their subscribers. One of the things it does is change every one of those clickable links. It will no longer send you to their website, to an online newspaper, or wherever it was. It will send you to a specially crafted link on a website run by the mailing list provider, probably quite a long URL. If you click on that URL, you'll be redirected to the website that the email author originally included.

Tracking

Why does the mailing list software do this? In a word, "tracking". Before redirecting you to the final webpage, their web server will log the fact that you've clicked that link. That means the mailing list owner can look at metrics - how many of their emails are opened, how many of their links get clicked on, which subscribers are most active in doing those things, and so on?

Opening

Did I just say they can see who has opened their emails?

Yes, they can, but not with complete reliability. Many mailing list tools will insert what's called a "beacon" file into the email. It's a very small (1 pixel x 1 pixel) transparent image, so you'd never see it. But it's loaded from a website using another specially crafted URL. Again - if that image is shown as loading, the mailing list provider can track it back to the exact email and the specific recipient. They can conclude that you opened your copy of that mail. They may also work out some things like what browser or email client you were using (from a think called the "User Agent string").

It's not 100% reliable, because some email software blocks images for exactly this reason.

Unsubscribe

There's one special link in most mailing list emails. It's there because it has to be, in order to comply with anti-spam regulations. It's the "unsubscribe" link. Click that link, and you'll be removed from the mailing list. With some mailing lists, this triggers an email to the recipient, so they can confirm they wanted to unsubscribe. With most, it just does it for you then and there (either asking for confirmation, or not).

What happens if you forward that email to a friend?

So what happens if you forward that email? A number of statistics-distorting, but not terribly serious curiosities:

• If your friend opens the message, and they trigger the tracking beacon, it looks like you opened the email. You'll look like an avid reader, potentially reading each message dozens of times.
• If a friend clicks on a link, it will be tracked as you clicking on the link. In fact, you're the kind of reader the mailing list operator really wants - you're reading every email many times, clicking on all the links.

But there's also something more nasty:

• What if your friend clicks that "unsubscribe" link? It's a unique link for you, so the result is that you are unsubscribed from the mailing list. Oh. (They might do this maliciously. More likely, they'll do it by accident, thinking they're unsubscribing from your mailings, not realising they're unsubscribing you from the original mailing.)
• What if your friend doesn't like the email, but also doesn't realise it came from you. They report it as spam. The trouble is, the email came from you, so it looks to the spam blacklist maintainers as if you were the one sending spam. Not cool.

How do you forward your mailing list content to a group of friends?

Is there a way around this? There is.

If you're just sending the odd message to the odd friend, simply make sure you remove the "unsubscribe" links first.

But if you're regularly sending a round-up of news or special offers to a large list of your own contacts, here's the way to do it.

• Set up your own mailing list. Use a provider like MailChimp for this, or Mailman if you have website hosting that gives you this with the package.
• Configure the list. Set the description text so that people will know that this is to send on aggregated news from other sources. As friends are added to the list (by you, or by themselves), they want to know what they're signing up for.
• Add your friends to the list, or email them the sign-up link so they can do it themselves. Remember, to be spam-legislation compliant, they need specifically to opt in to the list, so don't try to bypass that for them.
• Copy and paste the content of any messages you want to send on to the list. Make sure any "unsubscribe" or "manage my subscription" links are removed first. Also make sure any "view this message in your browser" links are removed - for the same reason.
• In an ideal world, if you can be bothered, resolve the links within the email. That's to say, click on the link in the email you received, and replace the link within the email so that it no longer contains the magic "track then redirect" link but the actual target website link itself.

And that's it. Then, if your friends don't want to receive your news roundups any more, they will have unsubscribe links within the email that will do all of this for them.