Occasionally when troubleshooting DirectAccess connectivity issues I will encounter a scenario in which a client will have an established DirectAccess connection, but DirectAccess does not appear in the Network & Internet settings window in the user interface.
In addition, the Get-DAConnectionStatus PowerShell command returns the following error.
Network Connectivity Assistant service is stopped or not responding.
This commonly occurs when the Network Connectivity Assistant service (NcaSvc) fails to start. The issue can be easily resolve by simply starting the NCA service using the following PowerShell command.
Start-Service NcaSvc
Once the service has been started, DirectAccess will appear in the Network & Internet settings window.
Additional Resources
Planning and Implementing DirectAccess with Windows Server 2016 on Pluralsight