Sending an encrypted e-mail in Microsoft Outlook is normally not as simple as clicking the icon, especially if you and the recipient do not belong to the same organization. You can try, but you will most likely be given the following message:

In order to send encrypted mail, Outlook needs a certificate with the recipient’s public key. A common way to get a hold of the certificate is by asking the person to send you a signed e-mail. It is also possible to send a certificate as a file. Here are step-by-step instructions for each case.

From a signed e-mail

1. Open the signed e-mail.

2. Right-click the sender’s name or address at the top of the e-mail.

3. Click Add to Outlook Contacts. A window with the contact’s information opens. If the contact already exists, you will have to confirm that you would like to update the information.
4. Click the Certificates toolbar button and check that the certificate is listed in the Certificates (Digital IDs) box.

5. Click Save & Close.

6. Send the encrypted e-mail.

From a file

1. Create or open the contact to whom you want to send the encrypted e-mail.

2. In the contact window, click the Certificates toolbar button.

3. Click Import…

4. Find and select the certificate file in the Locate Certificate window and click Open. The certificate will be listed in the Certificates (Digital IDs) box.

5. Click Save & Close.

6. Send the encrypted e-mail

If you still can’t send the encrypted e-mail…

1. Open the contact.

2. Click the Certificates toolbar button.

3. Select the listed certificate and click Properties…

4. In the Certificate Properties window, click the Details tab.

5. Check the Subject field for the recipient’s e-mail address. If it is different from the address that you are trying to send to, you will see the “Encryption Problems” message. If possible, try sending the e-mail to the address in this field.

6. Check the Key Usage field for “Key Encipherment” or “Data Encipherment.” If this is not present, it could be a cause for Outlook not to send an encrypted e-mail. Try to obtain a certificate intended for encryption.

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This entry was posted on Tuesday, October 28th, 2008 at 5:59 pm by Mike Markiewicz and is filed under Tutorial Tuesday.