S/MIME certificates

Mit S/MIME-Zertifikaten können E-Mail-Identitäten geschützt, E-Mails digital signiert und verschlüsselt versendet werden.

Is it possible to use one S/MIME certificate on several computers, e.g. workstation and laptop?
Yes, the certificate can be used on several devices. To do this, the certificate must only be exported and then imported on the other devices. Important...
Sun, 21 Mar, 2021 at 2:04 PM
Where do the S/MIME certificates have to be installed?
The S/MIME certificates must be installed directly in the e-mail client. Instructions for installation in the most common clients (Microsoft Outlook, Lo...
Sun, 21 Mar, 2021 at 2:05 PM
Where can I check if the certificate has been installed correctly?
If the S/MIME certificate has been installed correctly, it can be seen in the certificate directory of the browser or your system. The certificate must be i...
Sun, 21 Mar, 2021 at 2:07 PM
How can I see whether an e-mail has been encrypted or signed?
In the header of the e-mails, symbols indicate whether the e-mail has been signed or encrypted. An envelope stands for signature and a lock for encrypti...
Sun, 21 Mar, 2021 at 2:08 PM
How does the exchange of keys take place?
To activate encryption, a signed e-mail must first be sent to the recipient. The recipient then replies with an e-mail signed by him or her. Only now can bo...
Sun, 21 Mar, 2021 at 2:09 PM
How is the encryption or signature of the e-mails carried out?
The signature and encryption of the e-mail can be permanently set in the e-mail client. Note: E-mails can only be encrypted if the recipient also has an...
Sun, 21 Mar, 2021 at 2:10 PM
My certificate has expired. Can I still read encrypted emails?
Yes, as long as the sender's key was stored during the validity of your own S/MIME certificate. With new contacts, of course, the key can no longer...
Sun, 21 Mar, 2021 at 2:11 PM
I no longer have my S/MIME certificate. What now?
If you do not have a backup of your certificate, you only have to have the S/MIME certificate reissued. After a "reissue", the same procedure app...
Sun, 21 Mar, 2021 at 2:12 PM
The keys have been exchanged. However, the recipient cannot read my mails. What is the reason for this?
It is very likely that you have an old or incorrect key for the contact. To fix this, delete the contact AND the saved certificate from your email client an...
Sun, 21 Mar, 2021 at 2:14 PM
When sending an encrypted e-mail, I get the message that the e-mail could not be sent. What is the reason for this?
Either the key exchange has not yet been completed or the contact does not use an S/MIME certificate.
Sun, 21 Mar, 2021 at 2:15 PM