A signature is not applied for one or more users


You have applied a signature for a user. When the user sends an email, the signature is not applied on the received message.


A common reason for this issue is that a group has been specified when creating the transport rule and connectors via the Exclaimer Cloud portal, and the user in question is not a member of the specified group.

This issue can also occur if there is a difference between the user's primary SMTP address, and their mail field in Office 365. The Office 365 mail field should match their primary SMTP address however, we occasionally see cases where the Office 365 mail field contains incorrect data (typically in hybrid environments or where AD sync is used).


There are three possible solutions for this issue:

Synchronize data manually

Performing a manual data synchronization ensure that users and group memberships are synchronized from Office 365. To do this:

  1. Log into the Exclaimer portal (portal.exclaimer.com).
  2. Click the Launch button.
  3. Click the Settings button at the top of the page.
  4. On the Data Synchronization tab, click the Start button under the Office 365/Azure Active Directory Synchronization heading.

Check conditions of the Office 365 transport rule

The sender must meet the conditions of the Office 365 transport rule which redirects the message to Exclaimer Cloud. If the message is not redirected then it won't be processed by Exclaimer Cloud and so no signature will be applied. To check the current conditions of the Office 365 transport rule, follow the steps below:

  1. Sign-in to the Office 365 admin portal (https://portal.office.com) as an administrator.
  2. At the Home page, click the icon at the top left of the screen: 


  3. Select the Admin option from the shortcuts panel or menu:


  4. Under Admin centers, select the Exchange option:


  5. The Exchange admin center is displayed.

  6. From the left-hand navigation menu, select mail flow:


  7. The mail flow page is displayed with a row of options in a menu bar at the top - the default option is rules:


  8. Double-click the transport rule which is sending messages to Exclaimer Cloud (typically this is called Identify messages to send to Exclaimer Cloud). Settings for the rule are displayed.

  9. Check for the condition named The sender is a member of… If this exists, make a note of the group that is specified as the condition's value - for example:


  10. Ensure that any users for whom the signature is required, are actually members of this Office 365 Group.

Check for incorrect data in the Office 365 mail field

To resolve this issue, please try steps below:

Verify that the Office 365 mail field contains incorrect data

To verify that data in the Office 365 mail field is incorrect, follow the steps below:

  1. Browse to http://graphexplorer.azurewebsites.net.
  2. Sign in and authorize access using your Office 365 administrator account.
  3. Update the following link with your own details (as indicated):
    For example:
  4. Copy/paste the updated link into the GET field.
  5. Click GET.
  6. Once you have a response, scroll down and locate the mail field. This should show incorrect data for the user - for example:

    Locate the Office 365 mail field

  7. If the mail field does not show the user's primary SMTP address, follow steps below to delete incorrect data and synchronize. If the user's primary SMTP address is shown in the mail field, please raise a support ticket.

Delete incorrect data and synchronize

If you complete the verification process described above and find incorrect data in the Office 365 mail field, follow steps below to resolve the issue and ensure the user is correctly recognised by Exclaimer Cloud.

  1. Access your Active Directory and delete the user's alias address which was shown in the mail field.
  2. Run an AD sync with Azure. This should update the mail field to the user's primary SMTP address.
  3. Once the sync is complete you can add the user's alias again, if required.
  4. Run a synchronize task from the Exclaimer Cloud portal:
    • Go to Settings on the main page.
    • Under Office 365/Azure Active Directory Synchronization, click Start.
  5. Once the synchronization task is complete, you can retest. If this process does not resolve the issue, please raise a support ticket.


Haven't found a solution to your problem?

Please click the button below, login to the Exclaimer Cloud portal and raise a support ticket. A member of the Exclaimer Support team will then be in touch.

Raise a support ticket