Turn on TLS 1.0, TLS 1.1, and TLS 1.2 in Advanced settings and try connecting to https://127.0.0.1:51383 again. If this error persists, it is possible that this site uses an unsupported protocol or cipher suite such as RC4 (link for the details), which is not considered secure. Please contact your site administrator.
Change settings
I get the above message after upgrading to the latest beta firmware. The settings are in fact already turned on in IE. What to do next? Is this a known problem?