MailChimp’s Inbox Inspector is an add-on that lets you check your email campaign’s “score” with all the major spam filters. With one click, you can tell what the likelihood is of your email getting blocked by inbox spam filters, server filters (like Postini, BrightMail, MessageLabs, and Spam Assassin), and Gateway filters like IronPort. Here’s a screenshot of what the spam filter check report looks like:

If you’re like to learn more about the Inbox Inspector, click here or check out this demo video.

To learn more about how spam filters work (and how to avoid getting trapped), check out the Deliverability section of the MailChimp email marketing resource center:

• How Spam Filters Think
• How Email Firewalls Work
• Avoid AppleMail’s Spam Filter

But there are always going to be exceptions. You will inevitably come up with an email campaign that’s very image heavy. Perhaps it’s for a big splashy product promotion. Or a big e-coupon. Or some postcard. Whatever.

Mark Brownlow recently posted an interesting theory on how you can increase your chances of that email getting opened, and we wondered if it was possible for our customers to (easily) do this sort of thing in MailChimp…

A quote from Brownlow’s article:

So here’s the theory…

Do you need to design your email for image blocking when sending to someone who has opened your emails in the past? No, because they’ve already demonstrated that they have images enabled.

Anybody wanting to try image-rich emails safely could simply pull out a list of “people who previously opened at least one email from us” and send this group the image-rich mail.

Hmm. Is it possible in MailChimp to send “only to people on your list that opened a previous campaign”?

You betcha. Just create a segment of your list like this (click to zoom in):

This is a segment of people who have opened any campaign that I’ve sent in the past. The assumption is that they at least use an email program that handles images. And maybe they’re interested enough in my content that they’re actually more likely to open and enable images. Yeah, there are all kinds of catches here, but it’s worth a shot. Plus, we know you’re going to send an image-heavy campaign anyway. Might as well not do it blindly. Segment that list!

The problem was that these spam filters were also automatically clicking our one-click unsubscribe link. While it’s not a widespread problem (yet), we have started to receive calls about unwanted unsubscribes. We traced most back to Trend Micro.

Anyway, most people recommended a 2-step unsubscribe process in response to this. And that’s a logical recommendation.

But whenever I actually work up the energy to click an unsubscribe link, I want off. NOW. Taking me to a landing page where I have to click yet another button—or even worse—enter my email address again, is not acceptable. It just looks pathetic. Like it’s a lame attempt to keep me trapped on the list. Especially when the confirmation buttons are confusing:

“Yes, I don’t want to unsubscribe” and “No, I want to stay on the list.”

Our programmer (The Chad) came up with a novel workaround, allowing us to keep the one-click convenience, while using the 2-step as a fallback…

How it works

When you click a MailChimp unsubscribe link, it takes you to a landing page that has a JavaScript redirect on it. If you’re a human, and you’re using a browser with JavaScript enabled (most browsers), you won’t see this landing page. It’ll just say “You’ve been unsubscribed.” Basically, it’ll work like a one-click unsub link.

But if you’re a spam filter, you probably don’t have JavaScript enabled. So the redirect won’t kick in, which will leave the spam filter sitting at the landing page, requiring the 2nd click to confirm your unsubscribe. If you’re one of those cavemen using a browser with JavaScript disabled, that’s fine—it falls back to the 2-step process.