What is the requirement for the purpose of "SSL Client:YES" for the SSL certificate I purchase?

This defines the purpose of the certificate and whether it can be used as client certificate. The following is a sample of an expected output from the command: openssl x509 -in your_cert.filename -purpose

Certificate purposes:

  • SSL client : Yes
  • SSL client CA : No
  • SSL server : Yes
  • SSL server CA : No
  • Netscape SSL server : Yes
  • Netscape SSL server CA : No
  • S/MIME signing : No
  • S/MIME signing CA : No
  • S/MIME encryption : No
  • S/MIME encryption CA : No
  • CRL signing : Yes
  • CRL signing CA : No
  • Any Purpose : Yes
  • Any Purpose CA : Yes
  • OCSP helper : Yes
  • OCSP helper CA : No

Please ensure that the certificate you purchase has "YES" for SSL
client. As noted, this certificate can be used for both server and client purposes.