For OS X.3 (Panther) users

Please use Safari for best results.

Step 1: Download Certificate 1. Save it to your desktop.

Step 2: Download Certificate 2. Save it to your desktop.

Step 3: Go to Applications>Utilities folder and open Keychain Access.

Step 4: In Keychain Access, go to File>Add Keychain...

Step 5: Navigate to Macintosh HD>System>Library>Keychains and select X509Anchors and click on the "Open" button.

Step 6: Click once on X509Anchors keychain to select it. Then go to File>Import...

Step 7: Navigate to where you downloaded the two certificates. Select one and click on "Open".

Step 8: Again, go to File>Import... and select the second certificate and click on "Open".

Final Step: Visually check to see if the two certificates are in the X509Anchors keychain. If they are there, you can delete the two files from your downloads and quit Keychain Access.

Error message:

Some users are experiencing an error when installing the second certificate. This is caused because the certificate had already been installed in the correct keychain. The Keychain Access application won't reinstall it if it already exists.

If it happens to you, please just ignore it and visually verify the two certificates have been installed from the image above.