My recipient does not use PGP
If the automatic search for valid PGP keys does not yield any positive results, a green symbol will appear next to the recipient address, indicating that this person is a new Guard user.
This means your recipient will receive a free, temporary Guard mailbox on our server and your message will be transmitted to this mailbox, fully encrypted. The recipient will then receive a notification with a web link to a login form: and another e-mail containing the password for logging in.
Secure access with an optional PIN
Since the e-mail with the password will be transmitted without encryption, it is possible for someone else to capture this information.
For this reason, you should always secure access to the temporary mailbox with an additional PIN. This PIN will not be sent automatically to your recipient, but to you, the sender. You can then choose an appropriate way to let your communication partner know about the PIN, for instance by phone, text, messenger, or in person.
Handing over the PIN is something that needs to be done only once, and thus presents relatively little effort for considerable security gain. Exchanging any number of encrypted e-mails is convenient and easy to do once your communication partner has received the PIN.