Updated: Nov 7, 2018
Your Outlook on the web looks like this - no "D" icon on the top right when an email is selected. Follow the steps below to start tracking in Microsoft Dynamics 365.
1. Configure Email Server Profile with Server Type "Exchange Online".
2. Login as Global Admin to approve Email, Test & Enable Mailbox.
3. Select checkbox "if this mailbox was previously configured to sync with another org..."
4. Refresh Outlook on the web and you should see an email with the subject "Your mailbox is now connected to Dynamics 365". Notice the "D" icon on the top right. Your Outlook emails can now be tracked in Dynamics 365.
5. To open the Dynamics 365 panel, click on the "D" icon in your email.