Configuring Office 365 Mailbox Access

In order for Email Signature Manager to access the mailboxes hosted by Exchange Online, it is necessary to configure an Entra ID Application with the appropriate permissions and certificate. Clicking the Configure button on the Environment Configuration dialog launches a wizard that will guide you through the process of configuring this application; the wizard can either register a new application or ensure that an existing application is up-to-date.

The wizard uses the Symprex Application Setup Enterprise Application to perform the configuration of the Email Signature Manager Application and requires the following permissions:

1.User.Read: This allows the setup application to login as the specified user and read their basic profile (such as their email address).

2.Application.ReadWrite.All: This allows the setup application to read, create and modify the Registered Applications in your tenant.
 

The Email Signature Manager Application requires the full_access_as_app permission, to which admin consent must be granted to allow the application to sign-in silently. In addition, a valid certificate must be defined to authenticate the application (self-signed certificates can be used and the wizard can generate such certificates automatically); certificates have an expiry date, so must be periodically renewed.

Once the application has been successfully configured, it is recommended to click the Test Connectivity... button to test the mailboxes in your Exchange Online tenant can be accessed as expected.

Note: There can be a delay between completing these wizard and the configuration being applied. You can always use the Configure button to re-run the configuration process if required.

At any time, you can login to Azure Portal and navigate to the App registrations blade to review, modify or delete the Email Signature Manager Application. In addition, if you prefer to manage your app registrations yourself through the Azure portal, the details of the app to be used by Email Signature Manager can be entered manually into the wizard.

Note: Once the configuration process has been completed, you may remove the Symprex Application Setup application from the Enterprise Applications blade in the Azure Portal if you wish.