Subsequent archiving of private keys
For the encryption of email messages, companies typically use the Secure / Multipurpose Internet Message Extensions (S/MIME) standard and provide their users with appropriate certificates for this purpose.
An important aspect here is that the users' private keys should be secured centrally - in contrast to the signing certificates that are otherwise mostly used. Incoming messages are encrypted for a specific private key and can only be decrypted again by this key . Thus a backup of these keys must absolutely be available - this is also indispensable for synchronization to mobile devices . For this purpose, the Microsoft Active Directory Certificate Services offer the private key archival function.
But what if private key archival has not been set up and users have already requested corresponding certificates?
