backup all certificate in Firefox in Windows 7

 To backup all certificate in Firefox  in Windows 7
Select "Tools"->"Options" , then select "Advanced" -> "Encryption" -> "View Certificates", choose the "Your Certificates" tab and click on "Backup All", choose a name for this backup file, provide a backup password and save it in local computer.

To restore the certificate in another computer, in FireFox, same process, using "Import" instead of "Backup All".

I backup local computer certificate to
C:\Users\jiansen\Desktop\real-server\local_certifcate\localpc.p12