Unhandled server error when trying to create an account

Hi there,

I just installed bitwarden on our server as shown here.

Everything went well and the server is running. But if I want to create an account and click submit after a while (20 seconds) I get an Error:


I do not know what it means and I did not find anything in the log file, maybe I am looking within the wrong one. Email Configuration should be ok because these values are working on another server app.

What could be the reson?