Unable to start HTTPS service on non-standard port

I'm trying to run bOS server on specific tcp/ip ports. i.e. http on 9080, https on 9443. According to manual i have edited BOSService.exe.config as follows:

<appSettings>
<add key="EventServiceUri" value="net.tcp://localhost:16100/" />
<add key="HttpsServiceUri" value="https://localhost:9443/" />
<add key="HttpServiceUri" value="http://localhost:9080/" />
<add key="RPCServiceUri" value="http://localhost:81/" />
<add key="EnableRPC" value="True" />
<add key="ClientSettingsProvider.ServiceUri" value="" />
</appSettings>

But https connection does not work, http works fine. Changing back to 443 brigns it back.

I have already tried other ports, firewall is disabled. Checked on Windows 10 and Windows Server 2008 without success.