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I have a cert.cer certificate file for my Mozilla Firefox. I don't have any clue how to go about installing it for my system. Any guidance would be of great help.

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up vote 3 down vote accepted
  1. Go to the Firefox menu → EditPreferences

  2. Click on the Advanced tab

  3. Click on the Encryption tab below Advanced tab.

  4. Click View certificates

  5. In the Certificate manager window, Click on the Import button. Then locate the .cer file, and then click Open. The cert file will be imported.

Hope this will help.

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I am able to access the websites which were blocked for me but still am not able to ping the url from terminal or either telnet it . Any idea ? – Aayush Sep 18 '12 at 7:03
You cannot ping an "url". If the url is, then you can ping, but not or – January Sep 18 '12 at 7:27

If you are familier with CLI mode..

then you can just run below command

sudo cp -rvf /path/of/abc.cer /usr/share/ca-certificates/mozilla/abc.crt

Remember one thing... you have to rename that cer file into crt file like above command.

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