In the web app, on the nav bar, click the Options Options button.
In the Set Personal Options dialog box, click the Email tab, and then under Select, the email messages to track in Dynamics 365, click Configure Folder Tracking Rules.
In the Folder-Level Tracking dialog box, under Exchange Folder, click + New Folder Mapping, click the down arrow in the box that appears, and then select the folder you want to track.
If you want to link the folder to a specific record—for example, an account or opportunity—under Regarding Record in Dynamics 365 apps, click the Lookup button graphic., and then search for the record.
Repeat steps 3 and 4 for any additional folders you want to track and (optionally) link to regarding records.
When you're done adding and linking folders, click Save.
Greetings,
Peter