Search Server Database couldn´t connect with internal Database


I have installed Razuna 1.9.6 on my Qnap and I like to use the Search Server Database. If I try to change the configuration at the backend → general Configuration → Indexing → Configurate Search Server Database Connection → Razuna uses the internal database, I get the error: There is a connection error with your search server! If I use the server everything is fine, just the Search function doesn´t work… does anyone have an idea to solve that issue?

Is the search server running on localhost:443? From that error it is not.