Only import certs signed by yourself or someone you deeply trust!
Importing certs signed by untrusted person may cause great loss to you!
1. Internet Explorer (System cert pool)
For self-signed single website cert, you should add it to trusted root CA.
For self-signed CA cert, just add the it to trusted root CA. Then all websites certs affiliated to it are automatically trusted.
Trusted Root Certificate Authorities in left panel; Select
On menu bar, click
Action -> All tasks -> Import...
Next; Browse your certificate; Click
Yes to the warning.
BTW, IE might have one-day lag for the cert to take effect. You may modify computer date to verify it.
Chrome also uses system cert pool, so this should work for Chrome as well. Anyway I haven’t checked that.
2.1. For single website cert
Visit that site.
I Understand the Risk.
Confirm Security Exception.
2.2. For self-signed CA cert
Alt; In menu bar, click
Tools -> Options -> Advanced -> Encryption -> View Certificates.
Import...; Browse and open your cert.
Trust this CA to identify websites, or check all three; Click
Try visiting your site. If you encounter any problem, Firefox will tell you why in Technical Details.