When I navigate to the Unraid  Web GUI using HTTPS 443, the browser returns "This site can't be reached. [server] refused to connect" ERR_CONNECTION_REFUSED.  Wireshark capture shows the Unraid server is receiving a [SYN] packet and immediately replies with [RST,ACK].  Unraid acknowledged the connection but doesn't like something and closed it.  I've always used the GUI over HTTP 80 and to be honest I don't know if 443 has ever worked, but Settings=>Management Access has SSL/TLS set to Auto and HTTPS port is set to 443.  Unraid version is 6.9.1.  I'm not trying to connect from internet, just trying to connect from within local network with self-signed cert.  Any ideas?

Set use SSL to be no and see if there's any difference.   The unraid.net certificate is no longer supported on such an old OS version 

I'm not using an unraid.net cert; just the self-signed [server].local cert.  The irony is I went down this HTTPS rabbit trail while preparing to upgrade the OS.  I successfully upgraded to 6.11.5 and set SSL=Yes and it works.

 

The options are different now (No, Yes, Auto) vs. (No, Yes Strict).  Pre-upgrade with SSL=Auto, I saw nothing listening on 443.  Not sure why that was, but it's the reason for the [RST, ACK] reset packets.  Maybe I just needed to set SSL=Yes instead of Auto? Or maybe the upgrade resolved it?  Or maybe I'll never know?  ¯\_(ツ)_/¯

There were significant changes to how SSL is handled between 6.9 and 6.10, and the meaning of "Auto" changed, which is why it was renamed to "Strict".

 

So at this point you are on 6.11.5 and SSL is working as expected? 

 

If you would like to reach more about SSL in 6.11.5, see:
  https://docs.unraid.net/unraid-os/manual/security#securing-webgui-connections-ssl 

Yes, all is good now.  I almost want to revert to 6.9 for curiosity sake and see if simply setting SSL from 'Auto' to 'Yes' would have done it.  I never tried it.  I thought it would lock me out of the GUI.