Firefox: certificate is not trusted because the issuer certificate is unknown

Question

I'm working in a lab environment. I have a Windows-based CA and an SSL-secured website on IIS (on the same machine) with a cert issues from that CA.

When I browse to this site in Firefox using SSL, I get an error "The certificate is not trusted because the issuer certificate is unknown."

If I go to Tools -> Options -> Advanced -> Certificates -> View Certificates -> Authorities, my CA's cert is in the list. If I double-click that certificate, I get "Could not verify this certificate because the issuer is unknown."

Isn't the whole point of adding a CA's cert into the Authorities list to tell Firefox, "Hey... you know this CA, go ahead and trust the certs that it issues?"

How do I fix this problem?

Solution

Firefox is (most in his Desktop versions) very special in checking certificates. Where Google Chrome meets the root certificate, Firefox needs the FULL chain up to the root certificate in your crt file. And don't forget to prefix https:// to request!