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Using Email Signing Certificates With Outlook 2010

Document ID 125


Email signing certificates are digital signatures that verify the authenticity of an individual sending an email. Before a signing certificate can be used, it must first be requested and then installed. If you need to request a signing certificate, click here. For information on installing an email signing certificate in OS X, click here, or for information on installing a signing certificate in Windows 7, click here.

Once you have installed the certificate into your operating system, you can access that certificate with your email client in order to send digitally signed messages. These instructions are for setting up signing certificates in Outlook 2010 for Windows.


Using Email Signing Certificates 

Note: You must install your signing certificate. If you have not, please follow the instructions at Importing Email Signing Certificate - Windows before continuing with the instructions on this page.


1. In Outlook 2010, click on File in your tab bar, and then click on Options [fig. 01].

Choose File and then Options

[fig. 01 - Choose File then Options]


2. Click on Trust Center [fig. 02].

Click on Trust Center

[fig. 02 - Click on Trust Center]


3. Click on Trust Center Settings... [fig. 03].

Click on Trust Center Settings

[fig. 03 - Click on Trust Center Settings]


4. In Trust Center Settings, click on E-mail Security. Make sure you have check marks next to "Add digital signature to outgoing messages" and "Send clear text signed messages when sending signed messages." If you leave this second option blank, some email clients will be unable to read your signed messages. Click on Settings... next to the "Default Setting" entry [fig. 04].

E-mail security

[fig. 04 - E-mail Security]


5. If you have an email signing certificate already in use, you will have an entry on this screen under "Security Settings Name." If this is the first time you are applying a signing certificate, this will appear blank. In either case, click the New button [fig. 05].

New security settings

[fig. 05 - New Security Settings]


6. If you have multiple certificates, you will need to choose the correct one. If you have only one certificate, it will be the only one listed. Choose your certificate and click OK [fig. 06].

Choose certificate

[fig. 06 - Choose Certificate]


7. Once you select the certificate, several options on the Security Settings screen will fill in automatically. Make sure that the two check marks at the top of the screen are selected. Enter a Security Settings Name that you can remember. Click OK until you are out of the Trust Center settings [fig. 07].

Name settings and verify defaults

[fig. 07 - Name Settings and Verify Defaults]


8. When you send an email, your email signature certificate will sign the message, indicating that the message was sent by you and not someone impersonating you. This is signified by a red ribbon on the right hand side of your email header [fig. 08].

Signed message icon on sent messages

[fig. 08 - Signed Message Icon on Sent Messages]

If you have any further questions, please email or call us at 979.845.8300.

Document ID 125
September 23, 2013
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