When I try to import a second s/mime certificate in thunderbird it failes with the following message: "The PKCS #12 operation failed for unknown reasons." The first import works fine, but the second one doesn't. Both are created with the same script, which is using the same ca. It creates the key and the csr, signs it with the CA and put it in the p12 file. So the both differ only in the used email and the cert/key. I've tried it with the cert containing the full chain and without. No success. It's not possible for me to import it. Is there any point in thurderbird which breaks the import? A good reason I don't see?? :)