I'm trying to understand the S/MIME implementation, and maybe I'm wrong. I'm so stuck that I will try to explain ... Sign a mail works as I thought it would work. But, I supposed that when you send a ciphered email, you're using the Public Key of receiver, who has the Private key for decryption. So I supposed that outlook would use the certificate that you introduce on "Contact - Certificates".
But I see that the cipher's certificate, using Office 2007 and Office 365, it's always the same: the sender certificate.
I mean, I send a ciphered mail to a contact, for who I have a certificate configured on Outlook. But the receiver can not open it because it was ciphered with my certificate, not his (In fact I can open it on his computer, plugin my smart card on his card reader).
¿Could someone give me an advice about this?