About the Data Watchdog


When importing contacts in a file, it may be the case that the data isn't as clean, reliable or as safe to send to as you have reason to believe.

This is why we've created the Data Watchdog, a unique checkpoint that is on the lookout for any such questionable or risky data. After all, we don't want anyone to be guilty of email abuse; it damages reputation and deliverability.

This is why you'll encounter the Data Watchdog whenever you import contacts.

How the Data Watchdog works

The Data Watchdog is a powerful and intelligent analysis tool unique to our application, protecting our sender reputation and your delivery rates. No email address makes it into the system without being checked by the Data Watchdog first. Using a complex set of algorithms and checks, the Data Watchdog predicts, detects and prevents email abuse.

Launched in April 2009, the Data Watchdog has completed an astronomical number of checks, helping to safeguard against users sending to email addresses that might cause damage to our and your reputation. It alerts us to users possibly trying to send to email addresses that they may not have permission to send to, and which may then cause complaints.

Twofold protection

Data Watchdog protects in multiple ways:

  • Protects the sender who's uploading the data. By assessing and blocking problematic data, we're protecting you from complaints and potential ISP blacklistings, and guarding your all-important delivery rates.
  • Protects you from being affected by other users sending to potentially problematic data.

Therefore it’s designed specifically to protect ALL of our clients and potential recipients from difficulties caused by ANY user sending to suspect data. This is undoubtedly a good thing.

But data verification is still your responsibility

The Data Watchdog isn't a data verification tool, and shouldn't be relied upon as one. It's the responsibility of all users and their data providers to ensure the data they're sending to isn't problematic.

The Data Watchdog will block as suspicious any data it's previously seen and red-flagged, and it will block where possible data that exhibit known characteristics of suspicious data. As such, it's intended to help protect our reputation and yours. It's not intended to provide a substitute for the sender ensuring the quality and trustworthiness of their lists.

Data Watchdog outcomes

Immediately after checking your contact import file, the Data Watchdog will report back to you in one of the following three ways:

Your file has been cleared


What it means: Your file has been successfully checked and cleared for use. It doesn't contain any email data that unduly alarms the Data Watchdog.

What you need to do: Nothing. The data in your file has been analysed and judged to be clean and safe to send to. You can proceed as normal.

Your file has been flagged as 'at risk'


What it means: Your file has been checked and whilst not quarantined on this occasion, it has been judged that some of your email data is a cause for concern.

What you need to do: You're free to proceed and send to the contacts in this file but it's important to realise that you do so with the possible risk of email abuse. As it's important that you're diligent about where you source your data and how you collect permission for it, it would be a good idea to seek further advice on this from either our knowledge base or by contacting our support team or your account manager, if you have one.

Your file has been quarantined


What it means: Your file has been quarantined as there's a significant cause for concern with regards to the quality of your email data.

What you need to do: You'll need to either contact our support team or your account manager, if you have one, to discuss your data in more detail.

Have more questions? Submit a request


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    Please note - The watchdog system is based on the assumption that Dotmailer is only ever used for mass-emailing. It's not. When loading a short file (e.g. with only 5-10 recipients), then the header row (which is required not to have to manually match all the csv fields to Dotmailer fields) causes such file to get flagged or worse, quarantined, since obviously the header does not contain a valid email address. What are the alternatives?

    1)not having a header row  (as mentioned, it adds an extra/ unnecessary step to the process)

    2)manually typing those personalised emails in outloook/gmail

    Both options are wasting precious time. Hopefully in the future, Dotmailer will take CSV headers into account - for instance, a tick box at the time of import specifying that "the first row contains headers" - a rather common feature for imports.

    Thank you

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    The issue reported by Linda still happens. When I load 2 data rows plus a header row I get 'RejectedByWatchdog', but when I load 20 data rows plus a header row (including the data rows rejected earlier) I don't get an error.

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    Hi Mike,

    This would appear to be a valid Data Watchdog response and not an issue connected to the header row.

    Getting rejected would indicate the Data Watchdog has reason to be concerned by the overall quality of the data in the file, which in this case would be the one email provided.

    The clearance of the 20 data row file indicates that the Data Watchdog wasn't sufficiently concerned with the overall quality of the data provided. This indicates that the large majority of the emails cause no concerns to the Data Watchdog.

    You might want to try this out by uploading a single contact in this way using an email address that you know to be fine. You should find the file gets cleared.

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    Hi Neal,

    We have enabled the integration between Dynamics 365 and DotMailer. When we create a Marketing List in Dynamics 365 and it is synchronised to DotMailer, does the Watchdog process run on it as well? If so, where could we see the results?


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    Hi Ramon. Thanks for your question. Yes, the Watchdog process does run on this, as dotmailer for Dynamics uses dotmailer's API to import contacts.

    You should be able to find the Watchdog import report by navigating to the person-and-cog icon in the top right corner of the app, selecting 'Notifications' from the menu and clicking the link that's available where it says 'Your contact import has finished. The import report is now available.' This will take you through to the report. However, let me know if you can't see what you're expecting to.

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    It seems Linda's most important comment has been overlooked:

    "for instance, a tick box at the time of import specifying that "the first row contains headers" - a rather common feature for imports."

    Just that, every other area I import data is a tick box for 'includes header row'

    Could dotmailer look at implementing this?

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    Hi Matt. The good news is that this function already exists and you'll find it by clicking on the 'Change settings' button, when on the 'Mapping' stage of the contacts import process. The 'First row contains columns names' box will become available for ticking - https://support.dotmailer.com/hc/en-gb/articles/212211898-Importing-contacts-into-an-address-book#columnnames. Hope this helps.

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    It does help, thanks very much namesake :)

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    This is still broken for me and our HR Department are considering alternatives now. I upload a file with 2 valid email contacts in the same domain as me, I've tried the supported formats in csv, txt, xls, all UTC 8 and includes heading row (I ticked the box in advanced settings) and this still goes to quarantine with no means of undoing it at this point. What's frustrating for users I reckon is that there's no follow-up guidance for the scenario E.g. if you have validated your file and contacts but it still gets quarantined, examples of good data, do's/dont's etc. Clearly I'm not the only one who's exprerienced the issues.

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    Hi Stephen. This, unfortunately, was a rare case in which the Data Watchdog had genuine cause for concern around these email addresses. The best action to take is to contact our support team after a file’s been quarantined (as we advise above, and as I appreciate you did), and they’ll be able to advise on any problems with the quality of data, and they'll be able to manually clear a file if they can.