Cannot cereate account on self hosted BW

I’ve installed BW on a virtual machine on my laptop. Domain is obviously fake and I point to the domain by adjusting by hosts file.

I can open BW web interface, it does give me a form to create an account but when I try I get error message (red balloon in the top right of the browser window) " An error has occurred. An unhandled server error has occurred."

Any ideas were to look further in order to get to the bottom of this?