>pki-chain.pem contain the concatenation of our 3 level pki hierarchy >( cat itClass1.crt > pki-chain.pem ; cat itClass2.crt >> pki-chain.pem ; >cat itClass3.crt >> pki-chain.pem ) Did you find somewhere in openssl documentation that you can mix .pem and crt formats like that? Ivan Kalik Kalik Informatika ISP