We sometimes have to re-certify users or change their id after name-changes etc.
After this some users find that they cannot read incoming encrypted emails. This happens when the senders of these emails have this user in their local address book. Since the id/certificate has changed but the people have not been informed, the user’s record in their local address book contains the old public key certificate. Hence the user cannot read the email sent to them.
Is there any way to get around this? For example is it possible to keep the old key plus the new one?