By registering a user certificate in the Address Book, you can send e-mail that is encrypted with a public key which prevents its content from being altered during transmission. You can also prevent sender impersonation (spoofing) by installing a device certificate on the machine, and attaching an electronic signature created with a private key. You can apply these functions separately or, for stronger security, together.
To send encrypted e-mails, both the sender (this machine) and the receiver must support S/MIME.
To use S/MIME, you must first specify [Administrator's Email Address] in [System Settings].
Compatible mailer applications
The S/MIME function can be used with the following applications:
Microsoft Outlook 2003 and later
Thunderbird 3.1.7 and later
Windows Live Mail
If an electronic signature is specified for an e-mail, the administrator's address appears in the "From" field and the address of the user specified as "sender" appears in the "Reply To" field.
When you send e-mails to both users whose mail clients support S/MIME and users whose clients does not support it, e-mails for S/MIME clients are encrypted while those for non-S/MIME clients is sent as plaintext.
When using S/MIME, the e-mail size is larger than normal.
For details about using S/MIME with the scanner function, see "Security Settings to E-mails", Scan.
For details about using S/MIME with the fax function, see "Encryption and Signature for Internet Fax/E-mail", Fax.