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So, you’ve just hit the send button on a campaign to thousands of subscribers. Following the initial rush, hair-on-end paranoia kicks in. Are all the links correct? Is the subject line typo-free? Then, you see it – a phone number in the copy is wrong. The taste in your mouth quickly turns metallic.

Pretty much any experienced email sender has gotten something blatantly wrong in their HTML email content, at one time or another. So it isn’t entirely surprising that some of the clever folks amongst us have thought up a “Plan B”, should it be necessary to rush through a change on a live campaign. Such a backup plan was suggested by cool customer Ben Carver, who adds a transparent image which can be “swapped out” at a moment’s notice. As a result, he can throw a banner image, or similar message into email newsletters, should something go wrong.

Adding a Plan B to your email code

Taking advantage of the fact that many email clients repeatedly download images whenever an email message is opened in the inbox, the basic idea behind Plan B is that an image can be hosted on your server, then swapped out for one with a different message and different dimensions, if required. For example, you may have a 1px x 1px image on your server initially, which can then be replaced with say, a 600px x 150px banner. From a code perspective, this looks like so:

<img src="" cm_dontimportimage />

Two important things to note here – no image dimensions have been defined and the cm_dontimportimage attribute has been added to tell our app to not host the image on our servers. If ‘’ is say, a transparent image, it should be invisible in most email clients.

That said, an alternative to adding an image is to use the same technique with an existing banner image in an email, similar to adding dynamic images to an email campaign.

Using Plan B as your preheader

Having a 1px x 1px image can also serve a dual purpose – for example, you may want to add a preheader (otherwise known as a Johnson box) to your email message. The Plan B image is ideal for this, as ALT text within the <img> tag will show up in inbox previews, as long as this tag immediately follows <body> in the HTML email code.

Going beyond the boo-boo

While this is a neat idea that many may consider using for adding last-minute corrections, there are ways it can be used proactively, too. For example, let’s say you want to inform subscribers of a newly-released product, soon after a email campaign has gone out. Or for the benefit of those who use their inbox as a ‘to-do’ list (yes, that’s me), you may want to add a new banner reminding recipients that some action needs to be taken, say, a few days before a sale ends or event registration closes. In these cases, it’s possible to change your message in both subtle and not-so-subtle ways to get your subscribers to engage.

Many thanks to Ben for generously sharing this tip with us. So, how about you? Do you have a “Plan B”, or technique for ‘foolproofing’ your email content? Let us know in the comments below.

This blog provides general information and discussion about email marketing and related subjects. The content provided in this blog ("Content”), should not be construed as and is not intended to constitute financial, legal or tax advice. You should seek the advice of professionals prior to acting upon any information contained in the Content. All Content is provided strictly “as is” and we make no warranty or representation of any kind regarding the Content.
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