안녕하세요.

Let's Encrypt를 이용해 인증서를 발급받는데는 성공하였으나, .crt와 .key 따로가 아닌 한번에 .pfx를 줘서

타 프로그램에 사용을 하지 못하는 상황입니다 ㅠㅠ 

구글링 결과, OpenSSL 프로그램을 이용하여 추출을 시도해 보았습니다.

하지만 오류를 뱉어내며 작동하지 않습니다ㅠㅠ 

OpenSSL> pkcs12 -in filename.pfx -clcerts -nokeys -out clientcert.crt --password pass: password
Usage: pkcs12 [options]
where options are
-export       output PKCS12 file
-chain        add certificate chain
-inkey file   private key if not infile
-certfile f   add all certs in f
-CApath arg   - PEM format directory of CA's
-CAfile arg   - PEM format file of CA's
-name "name"  use name as friendly name
-caname "nm"  use nm as CA friendly name (can be used more than once).
-in  infile   input filename
-out outfile  output filename
-noout        don't output anything, just verify.
-nomacver     don't verify MAC.
-nocerts      don't output certificates.
-clcerts      only output client certificates.
-cacerts      only output CA certificates.
-nokeys       don't output private keys.
-info         give info about PKCS#12 structure.
-des          encrypt private keys with DES
-des3         encrypt private keys with triple DES (default)
-idea         encrypt private keys with idea
-aes128, -aes192, -aes256
              encrypt PEM output with cbc aes
-nodes        don't encrypt private keys
-noiter       don't use encryption iteration
-maciter      use MAC iteration
-twopass      separate MAC, encryption passwords
-descert      encrypt PKCS#12 certificates with triple DES (default RC2-40)
-certpbe alg  specify certificate PBE algorithm (default RC2-40)
-keypbe alg   specify private key PBE algorithm (default 3DES)
-keyex        set MS key exchange type
-keysig       set MS key signature type
-password p   set import/export password source
-passin p     input file pass phrase source
-passout p    output file pass phrase source
-engine e     use engine e, possibly a hardware device.
-rand file;file;...
              load the file (or the files in the directory) into
              the random number generator
-CSP name     Microsoft CSP name
-LMK          Add local machine keyset attribute to private key
error in pkcs12

혹시 원인을 아시는분 계신가요~

아니면 .pfx를 .crt와 .key로 분류해주는 프로그램이나 사이트를 알고계신분 있으신가요?

언제나 저급한 질문만 해서 죄송합니다 ㅠ