Web bug disarmed by Mailscanner

In conversation with my mail admin, would be very grateful to know the answers to the following to backup my request!

Would adding DKIM/SI DNS records help prevent Mailscanner/spamassassin from disarming the web bug?

If so, would they also need to be running a spamassassin plugin to recognise DKIM? e.g. http://www.dkim-reputation.org/spamassassin/

Or would whitelisting the IPs do it?

This is how it appears when I receive a test…

<img src=3D"http://www.mailscanner.info/images/1x1spacer.gif" width=3D"1" h=
eight=3D"1" alt=3D"Web Bug from http://DOMAIN.createsend.com/blah/blah.gif" />

I also note that message is not marked as spam but is disarmed

not spam, SpamAssassin (score=2.639, required 5, autolearn=disabled, HTML_MESSAGE 0.00, SARE_UNI 0.59, SARE_UNSUB06 0.73, URI_HEX 1.32

Grateful for any help/thoughts - thanks,

Paul :)

travisbell travisbell, 7 years ago

Hi Paul,

Adding domainkey's can certainly aid in providing a lower spam score, but won't always and isn't a "sure fire" way to do so. DKIM creates a level of trust between the sending server (us) and the domain name used as the from address. Obviously, if the content is still too spammy (or atleast SpamAssassin believes this to be true), there's not much you can do except change your content.

While I don't know for sure, it makes sense to me that in order to gain the benefits of DKIM within SpamAssassin, yes, you would have to install the DKIM plugin.

Now, as to whether that will prevent the web bug error, I don't think so. Based on my reading about what this is exactly ( http://www.mailscanner.info/MailScanner.conf.index.html#Allow%20WebBugs ) it looks like this is a feature MailScanner has to simply block small images and as luck would have it, our tracking image is being counted as one of these.

The only options I see for this issue, would be to try and whitelist our IPs (this very well might get passed all the way down to the Allow WebBugs option, or, simply disable the option all together. You can see a list of our IPs here:


Hoe that helps point you in the right direction…

Travis Bell
paulgroves, 7 years ago


Thank you very much for your helpful response.


200,000 companies around the world can't be wrong.

From Australia to Zimbabwe, and everywhere in between, companies count on 
Campaign Monitor for email campaigns that drive real business results.

Get started for free