title: .NET Active Directory authorization in 2 tier application
body: <p>Let's say we have a PC station (windows 10) joined to Active Directory and there is a user that signed in.</p>
  <p>I have an application (client layer connects straight ahead to database). Currently, The application prompts for login / password upon start, however I want to change that and if the current user is connected to domain (sign in the system), give him access right away without prompting for credentials.</p>
  <p>I can imagine that once user is logged to system, the account can be in the meantime disabled, or password needs to be changed or password expired. Since I don't have password for the account, the question is</p>
  <p>How Can I validate currently logged user in Active Directory to gauge whether I can give him access to the application or not?</p>