Currently Being ModeratedJan 2, 2013 3:14 PM (in response to lachla)
did you find the solution ?
I can sign emails but I have tried for days to no avail (OS 10.8., Mail 6.2) to encrypt emails.
When the sender signs the message the public key is not transmitted . I have tried to import public keys in my login keychain with the Terminal command
security import pub_key.pem -k ~/Library/Keychains/login.keychain
as described on
The pub key gets imported under a generic name. I renamed it to match the sender's original name.
Nonetheless the encryption lock in Mail is still greyed out.
It may be noteworthy that I can encrypt mails to any of my own emails accounts.
I have run out of ideas.