Importing Certificate in MacOS

  1. Click on the downloaded certificate under Downloads in your browser or in your file system.
  2. Click on Add in the next window.
  3. In the field Password, enter the passphrase to your personal certificate, which you created in Downloading the Personal Certificate.
    Figure 1: Enter the passphrase
  4. Click on OK.

    Your personal certificate is stored under Keychains, in the category Certificates.

    Figure 2: Certificate under Keychains

    All certificates which are not provided by Apple are not trusted by default.

  5. Double-click on the certificate.
  6. Open the tab Trust and select the element When using this certificate:Always trust.
    Figure 3: Always trust certificate
  7. Enter your administrative password and click on Update settings.
    Figure 4: Enter administrative password

    The certificate is marked as trustworthy.

    Figure 5: Trusted certificate

    Your personal certificate is imported automatically only by the default iOS mail client. If you are using another email client, please import the certificate manually according to the instructions of your email client.


In order to be able to read your e-mails on all your devices, you must install your personal certificate on every one of them. The supported operating systems and associated installation options can be found under Installation of the Personal Certificate.

Once you have installed your personal certificate on all your devices, follow the steps in Opening an Encrypted Email.