Secure email - import and use in Outlook 2019 and 365


Use these instructions to import a secure e-mail certificate (.p12 or .pfx) into Windows and configure it in Outlook


  • Secure e-mail certificate (.p12 or .pfx file)

  • Password to the Secure E-Mail Certificate

Import into the Windows certificate store


Double-click the certificate file .p12/.pfx


Click "Next"

Click "Next"
  1. Enter your password to your certificate file .p12/.pfx.

  2. After that click on "Next"

Click on "Next"
Click on "Finish"
Click on "Ok"

Configuration in Outlook

  1. Open Outlook

  2. Select the menu item "File" in the upper left corner.

After that, click on "Options" in the lower left corner.
Select "Trust Center".
Select "Settings for the Trust Center...".
  1. Click on "Email Security"

  2. Select the two checkboxes as shown below.

  3. Click on "Settings".

  1. Enter a name for your S/MIME profile

  2. Mark both checkboxes as shown below

  3. Select the certificate you want to use for signing and encryption.

  4. Change the hash algorithm to SHA256.

  5. Close all windows with "OK".

  1. Create a new message.

  2. Select the "Options" menu item.

  3. Check whether the "Sign" item is activated.

  4. After that, you can send a test message to yourself, for example.


Checking the signature

  1. Locate the message you just sent in the Outbox folder and open it.

  2. Click the signature icon on the right

  1. The signature is displayed as valid

  2. Close the window by clicking on "Close".

You have successfully set up and tested your signature in Outlook.