Browser version: Firefox 3.6.12 with numerous add-ons.
Take One: Miserable Failure
Open: Tool > Options > Advanced > Encryption (tab)
Open; View Certificates > Your Certificates
You should be on “Your Certificates” tab.
Press “Import” button.Browse to the directory where the certificate file is located. Choose it.
Following error message appears:
Take Two: Solution
A suggestion from some web discussion forum (https://bugs.launchpad.net/ubuntu/+source/firefox-3.0/+bug/198841) said that the “Torbutton” extension may be a cultprit.
First disable Torbutton. Open Tools > Add-ons > Extensions.
Browse down to Torbutton item
and choose “Disable”
When it comes back, attemp to load the certificate. This time it succeeds, prompting you for the certificate’s password:
Enter the password and pres OK button.
The confirmation message is displayed:
And then the certificate is listed in the local certificate store:
One can look at the details of that certificate:
Related local content: Installing SSL certificates – https://eikonal.wordpress.com/2010/12/01/installing-ssl-certificates/.