PKI Tutorials - Herong's Tutorial Examples - Version 2.04, by Dr. Herong Yang
Valid Certificate Required in Outlook 2007
This section describes how to request digital signature and encryption when sending an outgoing email message in MS Office Outlook 2007. An invalid certificate error message shows up if you don't have any personal certificate that matches your email address and is issued from a trusted root CA.
Now let's try to send a test email message with encryption and digital signature.
1. Run Outlook 2007 and click "New" to create a new test email message.
2. Click the Digital Signature icon and the Encrypt icon in the "Options" menu group under the "Message" menu.
3. Click the "Send" button. Outlook displays an error message:
"Microsoft Office Outlook cannot sign or encrypt this message
because your certificate is not valid." See the picture below:
Looks like I need good certificate that matches my email address and signed by a trusted root CA to be able to use Outlook S/MIME encryption and digital signature functions.
Last update: 2011.
Table of Contents
Introduction of PKI (Public Key Infrastructure)
Introduction of HTTPS (Hypertext Transfer Protocol Secure)
Using HTTPS with IE (Internet Explorer) 10
Perl Scripts Communicating with HTTPS Servers
PHP Scripts Communicating with HTTPS Servers
Java Programs Communicating with HTTPS Servers
Certificate Stores and Certificate Console
.NET Programs Communicating with HTTPS Servers
CAcert.org - Root CA Offering Free Certificates
PKI CA Administration - Issuing Certificates
Digital Signature - Microsoft Word 2007
Digital Signature - OpenOffice.org 3
Digital Signature Scheme for Email Messages
A Simple Email Message Example
Email Messages with Attachments using MIME
Email Messages with Digital Signatures using S/MIME
Encrypted Email Messages using S/MIME
Digital Signature and Encryption in Outlook 2007
Email Security Settings in Outlook 2007
►Valid Certificate Required in Outlook 2007
Message Security Properties in Outlook 2007
Firefox Extension - Gmail S/MIME