Login Prompt from the Web Client asks you for a password / can't login

Nodinite relies on Windows Authentication and uses integrated security and therefore the IIS and Windows must be properly configured with appropriate firewall settings in order to communicate with the domain controllers.

The proper setup for IIS and Windows is decribed here.

Link Comment
Is the Windows Identity really added either as a user or part of a registered AD Group? Not allowed, not welcome in Nodinite (!)
Perform locally on Nodinite server If it works locally then you do not have a problem with IIS, probably firewall and/or Windows related
Internet Explorer May Prompt You for a Password Microsoft KB Article
Verify Windows Authentication role is installed in IIS Windows 2012/R2 and also Windows 2016
role
This is the most common problem
Verify members of local policy 'Access this computer from the network'
policy
Provided image is Windows default, note Everyone is in the list

Next Step

Add or manage User
Add or manage Role

Users
Roles
Install Nodinite