Microsoft Outlook automatically encrypts email while using the mobile app. You may need to update your SSL settings if you’re using Outlook on another device.
- Click File
- Select Account Settings from the drop down menu
- Select the email account you want to edit then click Change
- Click the More Settings button then the Security tab
- Make sure the checkbox is selected next to Encrypt data between Microsoft Outlook and Microsoft Exchange
For more information, visit Microsoft’s support page