Make sure you have the correct Path to certificate. If so, try to generate a new certificate (from Configure).

Thank you very much Amirhossein.

I'm sorry. I think I made myself unclear.

I have successfully changed Ajenti's port to 8787 and am able to log in fine.

However, I want to further secure things by adding auth_basic to this so that anyone going to https://myajentiinstallation.com:8787 must first enter in a username/password for auth_basic, and then after entering the correct credentials, they see the normal Ajenti login screen.

Any ideas?

Thanks again!