Long block of hidden text - bayes poison?

Comments

17 comments

  • Geoff Schemel

    Bayesian Poisoning is a technique spammers use to try and defeat key-word based spam filtering.  Spammers basically put a large block of hidden text inside of an email that uses legitimate words to skew how the spam filter scores the email.  

    The way to work around this would be to avoid large blocks of hidden text within an email template. You could also experiment shortening the text blocks within the email.

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  • Liz Bauernfeind

    We are seeing this as well too. I don't have any hidden text in the emails & we are still getting the error. We opened a ticket with support too but have not seen any response. 

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  • Geoff Schemel

    I'd recommend reviewing the HTML directly in source view to be sure; but if your email templates are clean then it could just be something where the spam checker is misidentifying the issue.  If your email deliverability metrics are staying steady then you should be fine with ignoring the error.

     

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  • Amanda Jensen

    We are having this issue as well, out of nowhere. I always copy old templates and have had no issue with this before so I'm not sure why it's coming up now. We are seeing lower open rates and our emails are now getting delivered to the "Other" mailbox instead of the main one so I think it is causing an issue, but when I chatted with someone on help they said to ignore it and it wasn't a big deal. What am I supposed to be looking for in the HTML? I haven't changed/added any hidden text because I don't even know how to do that.

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  • Liz Bauernfeind

    Geoff, we used to use the Acoustic HTML quite frequently when issues arose. However, now that we are using the new message composer templates Acoustic has removed the ability to quickly check the HTML. We don’t want to have to download the file to search in another system…

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  • Brittney Jil

    We noticed this happening with one user last week. Now both of our users are seeing this message. Opening a support case. We used the same base templates over and over.

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  • Michael Hobley

    From my understanding, the rules that make up the spam health score come from a community-sourced dataset.  This can lead to false positives that come and go over time. We routinely have things that show up for 3 weeks and then disappear, only to show up again a month later.

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  • Caroline Daubitz

    Our team started seeing this error as well. We use the beta message composer and found that removing the preheader text removes the error message in the health check. Support said it was most likely a false positive after an Apache Spam Assassin update but I'm concerned about the potential risk to deliverability and open rates. Has anyone experienced a decrease in engagement metrics after seeing this error?

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  • firstName lastName

    Geoff Schemel This is actally a frequent issue that comes and goes, as you noted "it could just be something where the spam checker is misidentifying the issue". The same template will be used by clients and even a email created one week no issue with the spam check and then te next week or day even there is. Its a real issue for clients to know what is a real issue and what is a false positive. Unfortunately suppport arent great with this as they arent HTML code experts and how can they know if its a false positive or not. The issues have actually started to happen more and more and its not really worth reporting to support which means there is no point having it. Is there any way that someone at Acoustic can work onthe false positive situation with SPAM Assasin, if its integrated in the product there has to be some level of support. I can provide multiple examples from multiple clients and it looks like a lot of other people are having the same based on the above.

    This week its been the following and no doubt these will disappear again soon and pop back up at some point.

    1.5 Font too small to read, no rDNS
    3.4 HTML hidden text + other spam signs

    Also in testing see different results on different pods with the same template and was advised by support hat pod 7 has a more up to date spam filter?!

    Thanks Karen

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  • Amanda Jensen

    Caroline Daubitz We were told it wouldn't impact our deliverability and open rates, but we have noticed a slight decrease in our average open rate and we also noticed that our emails are getting sent to the "Other" inbox on Outlook so I'm not sure how it's showing up in other clients email inboxes. I'm sure this is what's impacting our open rate.

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  • Ryan Hoch

    We had a similar issue. It was fixed by doing the following...

    The issue is probably your hidden Preheader in the html code of your email template.
    Do a search in the Source code for "&nbsp;&zwnj;" or "preheader". It will probably be right after the initial <body> tag.
    If you have a large block of this "&nbsp;&zwnj;" trim it down. What worked for us is below. (I give credit to Litmus where I found the solution.) 

    <div style="display: none; max-height: 0px; overflow: hidden;">
    YOUR HIDDEN PREHEADER TEXT GOES HERE
    </div>
    <!-- Insert &zwnj;&nbsp; hack after hidden preview text -->
    <div style="display: none; max-height: 0px; overflow: hidden;">
    &nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;&zwnj;&nbsp;
    </div>

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  • Andrew Kim

    Has anyone else noticed that the most recent Litmus preview text hack doesn't work anymore? Acoustic is still saying "Long block of hidden text - bayes poison?"

    Has anyone found an updated 2022 hack?

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  • Michael Hobley

    Yes, it's happening with us as well. Very annoying.

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  • Andrew Kim

    Michael Hobley I'm assuming you're also have issues with gmail open rates?

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  • Michael Hobley

    No, we are primarily B2B and don't do a lot of gmail sends.  However, we started seeing the Bayes Poison spam item return a few days ago.  I know that the Spam Assassin has a community-contributed engine, but I hate that it disappears and then comes back.  We have about 60 active Campaign users who send email in 16 different languages, so having these types of "false positives" on our end just lowers confidence of our users.

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  • Mark Buckley

    I'm now seeing this issue after using the same template that I've used for several months and not seeing this error. I looked at the Pre-header and removed extra spaces "&nbsp;" I had and it made no difference. Hoping this is a false positive, as I had to send it anyway this morning.

    0.1 BODY: Multipart message mostly text/html MIME
    1 Font too small to read, no rDNS
    1.8

    Long block of hidden text - bayes poison?

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  • Ryan Hoch

    We had some lengthy alt and title tags that were causing the bayes notification. Cutting down on the length of the alt and title text seemed to help. Not ideal because the image may not have a full description. We just kept the most important info in the tags. 

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