Below CSR gives me an odd error with the standard openssl REQ command: openssl req -inform DER -noout -pubkey Error getting public key 140673482679616:error:10067066:elliptic curve routines:ec_GFp_simple_oct2point:invalid encoding:../crypto/ec/ecp_oct.c:312: 140673482679616:error:10098010:elliptic curve routines:o2i_ECPublicKey:EC lib:../crypto/ec/ec_asn1.c:1175: 140673482679616:error:100D708E:elliptic curve routines:eckey_pub_decode:decode error:../crypto/ec/ec_ameth.c:157: 140673482679616:error:0B09407D:x509 certificate routines:x509_pubkey_decode:public key decode error:../crypto/x509/x_pubkey.c:125: Even though the ASN1 of the public key looks correct to me: SEQUENCE (2 elem) SEQUENCE (2 elem) OBJECT IDENTIFIER 1.2.840.10045.2.1 ecPublicKey (ANSI X9.62 public key type) OBJECT IDENTIFIER 1.2.840.10045.3.1.7 prime256v1 (ANSI X9.62 named elliptic curve) BIT STRING (536 bit) 0000010001000001000001000011100100110011100111000110100010100101101000… OCTET STRING (65 byte) 0439339C68A5A333143592C0A36D053F31D3AF6ED18FB54F4747B9DFC6DB6ABC715561… What would be a good way to further debug this ? With kind regards, Dw -----BEGIN CERTIFICATE REQUEST----- MIIBPzCB5QIBADCBgDELMAkGA1UEAxMCQ04xCjAIBgNVBAUTATExCjAIBgNVBAYT AUMxCjAIBgNVBAcTAUwxCjAIBgNVBAgTAVMxCjAIBgNVBAoTAU8xCzAJBgNVBAsT Ak9VMQowCAYDVQQMEwFUMQowCAYDVQQNEwFEMRAwDgYJKoZIhvcNAQkBEwFFMFsw EwYHKoZIzj0CAQYIKoZIzj0DAQcDRAAEQQQ5M5xopaMzFDWSwKNtBT8x069u0Y+1 T0dHud/G22q8cVVh8sVcpLUortLxxesEXCddpx/EeuxP+MN/RymHTMrjoAAwCgYI KoZIzj0EAwIDSQAwRgIhAO+K+TFCdYxQg7aT+B3wIVa6CCYxM/mL4/WHSrwXujJy AiEA7UsbQT/YRKaFDPn/U9jdrJaUmKsqKJvGwN7YVaMGdeo= -----END CERTIFICATE REQUEST-----