Sending Digitally Signed or Encrypted Email Messages If the email was sent without access to your current public key, you will not be able to open the email.

When you open the email, you may be prompted to enter your CAC PIN. A gold padlock will appear in the far right corner of the message. When you receive an encrypted email message, a padlock appears next to the subject line of the email in your inbox. Once the email is open, the signer’s name appears after “Signed By” in the header of the message, and a red ribbon will appear in the far right corner of the message. When you receive a digitally signed email message, a red ribbon appears next to the subject line of the email in your inbox. Receiving Digitally Signed Email Messages

NDU technically supports encrypting and digitally signing out-going email using Microsoft Outlook 2010 and a DoD-issued Common Access Card (CAC) on NDU's network email servers (' following instructions apply only to the use of MS Outlook 2010 on NDU network-based Exchange email servers using a CAC.

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