In connection manager you can try to auto detect your Active Directory connection.
Options-->Connection manager-->Auto detect
At first, it will try to get the current user's domain forest and will then list all available domains and their domain controllers.
If automatic detection is successful, you will see a list of available connections.
Choose the one you want and press Select.
It will take you to a new connection creation window with the fields already filled.
Add additional options if needed and press Save.