(S/MIME in Microsoft Outlook für iOS aktivieren in deutscher Sprache hier klicken)
Enabling S/MIME in the client
S/MIME encryption is a reliable form of encryption to protect e-mail communication from unauthorized access and changes.
This article describes the use of signed and encrypted messages in Microsoft Outlook for iOS in combination with Hornetsecurity’s 365 Total Protection Business, Enterprise or Enterprise Backup solution.
The manufacturer offers cloud-based encryption technology that makes it possible to display, reply to or forward encrypted messages in Outlook for iOS in just a few simple steps.
Since the S/MIME functionality is deactivated by default in Outlook for iOS, it must be activated first.
- Open Microsoft Outlook for iOS
- In the application (on an Apple iPhone) click on your profile picture, then on the gear wheel ⚙️ to open the settings (On Apple iPad the gear wheel ⚙️ is always visible on the bottom left)
- Under E-mail accounts, select the account in which the S/MIME function should be activated
- Now open the item Security
- At the top is the S/MIME slider.
Switch it on and confirm the message with OK - Finish
Here are a few more pictures:



No further settings are then necessary in Outlook for iOS, since the client does not carry out the signature and encryption, but the server at Hornetsecurity. (Cloud-based encryption technology.)
With the setting shown above, encrypted e-mails can now be read and reused. If you use several Apple devices, such as iPad and iPhone, this switch must be activated once on each device so that e-mails are decrypted.
Encryption works by default in the native Mail app for iOS, as well as in Outlook for Windows and Outlook on the web. No action is required here.
*S/MIME = Secure/Multipurpose Internet Mail Extensions