Microsoft Office Tutorials and References
In Depth Information
Obtaining Other People’s Public Keys
To send an encrypted message to someone, you must have their public key. You can get this from a
signed message the person sent you. Their certificate is added to their entry in Contacts, and is
available for you to use to send encrypted email:
Open the digitally signed message.
Right-click the sender’s name or address in the From box.
Select Add to Outlook Contacts from the context menu.
If the contact already exists in your Contacts folder, Outlook will notify you. Select
Update Information of Selected Contact.
You can view a contact’s certificates by opening the contact and clicking the Certificates button in
the Show section of the ribbon. Outlook displays a list of the contact’s certificates, if there are any,
as shown in Figure 20.5. You can take the following actions by clicking the buttons at the right
side of this window:
n Properties: View the certificate details, including the name of the issuing company and
its expiration date.
n Set as Default: If the contact has more than one certificate, this command sets the one
that will be used as the default for encrypting messages to the contact.
n Import: This option lets you import a person’s certificate from a file. Certificate files have
the .P7C or .CER extension.
n Export: This option lets you export the certificate to a file. This can be useful when you
want to transfer a contact’s certificate to another computer.
n Remove: This option deletes the certificate from the contact information.
Encrypting and Digitally Signing Messages
It’s important to understand that encrypting a message and signing a message are two different
n Encrypting uses the recipient’s public key to encrypt the message and attachments so
that only the recipient can read them.
n Signing uses your digital ID to mark a message so that recipients can verify that it really
came from you.
A message can be signed, encrypted, or both.