Background
MS Outlook uses Digital IDs (sometimes called Digital Certificates) to automatically unlock encrypted e-mails utilizing the S/MIME format. For some products, such as Digital Indigo's Indigo Form Mail (IFM) you need to find the public key from a Digital ID.

PHP programmers also need the public key from a Digital ID if they plan to use the openssl_pkcs7_encrypt() function. Additional information is included in the output for uses such as the openssl_pkcs7_decrypt() command.

Getting The Digital ID Into A File.
We will assume your existing Digital ID is already installed in MS Outlook. In this case start Outlook and navigate as follows:
Tools -> Options -> Security (Tab) -> Import/Export Digital ID... (Button)

Next click the radio button aside of "Export Your Digital ID to a file..."

Use the Select button to select your certificate.

Click on the Browse button to choose where to save your Digital ID. (For example you may wish to save it on the Desktop as file digitalid.pfx.)

Choose a password for your certificate.

Now FTP the digitalid.pfx file to your Linux server. Be sure you have OpenSSL installed.

Run the following command to extract the components of your Digital ID to an ASCII file:
openssl pkcs12 -in digitalid.pfx -out chain.txt

The resulting file, chain.txt will contain a bundle of data extracted from your Digital ID. This includes your private key! BE CAREFUL!

You can now look through chain.txt. You will see your private key, the certificate for your public key, and some certificates for your Digital ID provider.

Copy everything from (and including) -----BEGIN CERTIFICATE----- to ---END CERTIFICATE-----. This is the public key, and what you use for IFM as well as the key variable on the openssl_pkcs7_encrypt() function of PHP.

Related Topics & Information None