STAS installation error 1057

Hi all

i am trying to install the stas sso application on a windows server 2016 domain controller.

i have followed the prerequisites guides in regards to firewall rules and log on as a service stuff.

i am getting an error 1057 after the installation process no matter what i do.

at some point i have added the dedicated user i was using to the domain admins group and i added this group to the log on as a service on the domain controller.

that didn't help at all.

what am i missing?

here are some screenshots for illustration:

current logon as a service on he domain controller:

here is the user accout i am using which is a member of domain admins:

here is the error screenshot:

(this error shows up after the installation process finishes, after i specify the username and password)