How-toImport an S/MIME Certificae in Thunderbird

This how-to explains how employees of the university can use an S/MIME certificate to sign or encrypt emails in Thunderbird.

Import certificate

Open Thunderbird and right click on the account for which you have received the certificate. In the context menu that appears, select "Settings" and then the category "End-to-end Encryption" in the dialog box that opens.

Screesnhot des Thunderbird Programms

Click "Manage Certificates" and the following dialog box will appear. Activate the category "Your Certificates" and click on "Import...". 


Screenshot des Thunderbird Programms

In the following dialog box, select your certificate and click on "Open" on the bottom right. When prompted, please enter the password specified when creating the certificate. You will be taken back to the dialog box seen in the previous screenshot. There should now be a certificate with your name under "GEANT Vereniging". Close the dialog box by clicking "OK" on the bottom right.

Auswahl des eigenen Zertifikats

You can now link your certificate with this account by clicking “Select” under S/MIME:

Screenshot des Thunderbird Programms

When asked whether this certificate should also be used for encryption, select "Yes".

Screenshot des Thunderbird Programms

Sign emails

Now every email you send will be signed. This is displayed in the window for composing an email if you click on the down arrow to the right of "S/MIME":

Screenshot des Thunderbird Programms