Dynamics NAV - Remove all users and allow a single login - user cannot login

USE [MyDB]
GO
delete from [dbo].[User]
delete from [dbo].[Access Control]
delete from [dbo].[User Property]
delete from [dbo].[Page Data Personalization]
delete from [dbo].[User Default Style Sheet]
delete from [dbo].[User Metadata]
delete from [dbo].[User Personalization]

Restart Service
Run as administrator if necessary