How to Proactively Check Email Addresses Against List Detective

Here are the three primary methods to check if an email address will be flagged by List Detective before a send.

1. Import to the All Subscribers List
If the import file contains addresses flagged by List Detective, an email with an attached file named "Import Result <datetime>.txt"  will be sent to the address specified in the [Email me upon import completion] field. Below is a sample of the attachment's content.

Example: The record on row 0 (the first row in the CSV) contains an address flagged by List Detective.

==============
Row Number    Error Number    Error Code       Error Details
0             59078015        ListDetective    ListDetective
==============

Previously, the Row Data column included the actual data from the record. However, the current default behavior is not to record this data. If you wish to enable the recording of row data, please open a support case with the relevant MID.

*Note: 
Please be aware that List Detective does not run when importing records into a Data Extension's Email Address field. You cannot use a Data Extension import to check for List Detective conflicts. The check only occurs at send time, at which point the subscriber is added to All Subscribers and flagged by List Detective, causing the send to be suppressed.

2. Use the REST API
You can check if an email address is sendable by making a request to the POST /address/v1/validateEmail route described in the REST API reference. In the example below, the local part (before the "@") is "postmaster," and the API response confirms it is flagged by List Detective.

Example:

<Request>

URL : POST https://<YOUR_TENANT_SPECIFIC_ENDPOINT>/address/v1/validateEmail

Body

-----

{
  "email": "postmaster@salesforce.com",
  "validators": [ "SyntaxValidator", "MXValidator", "ListDetectiveValidator" ]
}

-----

<Response>

Body

-----

{
    "email": "postmaster@salesforce.com",
    "valid": false,
    "failedValidation": "ListDetectiveValidator"
}

-----

3. Add an Email Individually via the Create Subscriber Wizard
You can check an individual email address by manually adding it through the Create Subscriber wizard. Navigate to [Email Studio] > [Subscribers] > [All Subscribers] and click the [Create] button. If an email address is flagged by List Detective, an alert will appear, and you will not be able to add the subscriber.

==============
Your SPAM filter does not allow this email address and cannot be added.
==============

Frequently Asked Questions
We receive a high volume of inquiries about the following topics. We recommend reviewing them first.

Q1) Can I get a list of all email addresses flagged by List Detective?
A) For security reasons, such as avoiding spam traps, we do not provide a comprehensive list of flagged addresses.

Q2) Can List Detective be completely disabled?
A) No, it cannot be completely disabled. However, it is possible to partially disable it for specific addresses or domains. If you can provide explicit proof of a subscriber's consent to receive emails, you can request that List Detective be disabled for those specific addresses. To do this, please open a support case with the local part (the string before the "@") or the domain (the string after the "@") of the email address. Our support team can enable the Custom List Detective feature to allowlist the strings you provide. Please note that we may deny requests if subscriber consent is unclear or if the request is for an obvious, well-known typo of a major domain (e.g., "gmai.com").

Q3) How can I determine if List Detective was the reason an email was not sent?
A) You can identify this using a Tracking Extract Data Extract Activity in Automation Studio.

Configure the tracking extract as described in the reference document and ensure the "Not Sent" option is checked. The extracted zip file will contain NotSent.csv, which lists subscribers who were not sent an email for each job and the reason why. Records where the "Reason" column shows "List Detective Exclusion" were suppressed by List Detective.

Reference: Tracking Extract Configuration in Automation Studio

Related Articles
For further questions about List Detective, please refer to the following articles:

validateEmail 

List Detective Overview

List Detective FAQ

Use Custom List Detective to restrict sending to addresses or domains in Marketing Cloud