SMTP AUTH Clients report in the new Exchange admin center in Exchange Online

The SMTP AUTH Clients report in the new Exchange admin center (new EAC) highlights the use of the SMTP AUTH client submission protocol by users or system accounts in your organization. By default, this legacy protocol (which uses the endpoint supports Basic authentication, and is susceptible to being used to send email from compromised accounts. This report allows you to check for unusual activity. It also shows the TLS usage data for clients or devices using SMTP AUTH.


By default, the report shows data for the last 7 days. If the report is empty, try changing the date range.

For permissions that are required to use this report, see Permissions required to view mail flow reports.

The overview section contains the following charts:

  • The volume of messages per day for each sending domain.
  • Message volume by sender*
  • Message sent by domain*
  • Senders by TLS protocol*

* If you hover over a specific color in the chart, you'll see the number of messages.

Overview of the SMTP AUTH clients report.

The Messages sent using SMTP Auth section shows the following information:

  • Sender address
  • Domain
  • TLS 1.0 (percentage)
  • TLS 1.1 (percentage)
  • TLS 1.2 (percentage)
  • Messages sent

To quickly filter the results, click Search Search icon. and start typing a value.

To filter the results by a date range, use the box. You can specify a date range up to 90 days.

For more advanced filters that you can also save and use later, click Filter Filter icon. and select New filter. In the Custom filter flyout that appears, enter the following information:

  • Name your filter: Enter a unique name.

  • Click Add new clause. A clause contains the following elements that you need to enter:

    • Field: Select Sender address, Domain, TLS 1.0, TLS 1.1, TLS 1.2, or Messages sent.
    • Operator: Select starts with or is.
    • Value: Enter the value you want to search for.

    You can click Add new clause as many times as you need. Multiple clauses use AND logic (<Clause1> AND <Clause2>...).

    To remove a clause, click Remove Remove icon.

    When you're finished, click Save. The new filter is automatically loaded, and the results are changed based on the filter. This is the same result as clicking Filter and selecting the customer filter from the list.

    To unload an existing filter (return to the default list), click Filter Active filter icon. and select Clear all filters.

Click Export to export the displayed results to a .csv file.

If you select a row, a details pane for the sender appears that contains the same information from the main report.