Before configuration, make sure that your digital ID (also called digital certificate) is already installed. If the certificate has not been installed, then you need to get a digital ID
Getting startedOpen Microsoft Outlook 2013 -> Options -> Trust Center -> Trust Center Settings… -> Email Security -> Encrypted Email -> Settings…
In the Change Security Settings, Choose your Personal Certificate (Signing Certificate) -> OK
And then set options like below:
Now you should be able to compose a signed email, in the Options tab
After the email is sent, you should see the SIGNATURE symbol like below in the sent folder:
Open the sent email, click on the Digital Signature Symbol, you should get following information: