Production setup behind reverse proxy


i am new on keycloak and have a local install of the server running.
But i am trying now about a week to get the keycloak running in a production setup.
it is impossible to reach the server using a public subdomain “”.
I have tries it with a reverseproxy under IIS in Windows 2012R2. The keycloak is running on the same machine under “myis . myserver . com”. Both subdomains are equipped with a LetsEncrypt certificate.
When calling the “” i get a 403 - forbidden error.
I am at the end of my latin… :frowning:
Also it is impossible to reach the server from another machine than the machine it is running on.
So far as i can see, keycloak is good for testing, but for production it is not usable.