Cant use cert imported into Thunderbird

I’ve followed the instructions for exporting the cert store cert to a file and importing it into Thunderbird. I can see the cert if I use the thunderbird certificate manager to view certificates (the only thing that looks odd is that the purpose is “”. When I try to sign an email “you need to set up one or more personal certificates before you can use this security feature. Would like to do so now?” pops up … to which I click Yes, which brings up the account settings dialog selected for security tab. If I hit select on signing I get the mesage “Certificate Manager can’t locate a valid certificate that can be used to digitally sign your messages.” Similar message for encrypting.

Where did I go wrong?!

(:SHY) Newbie is right! Please ignore this. I don’t know what that cert was that I exported from the Windows cert store, but it wasn’t the Comodo cert. You see, I used Firefox to retrieve the cert then followed the instructions. For anyone else who uses Firefox, don’t try to export the cert form Windows, export it from Firefox, then import into Thunderbird. Doh!


Can you please refer the following link for getting the certificate through IE and import it in to Thunderbird