Symptoms

When starting an application session in Awingu, an error is shown: 

A terminal license server could not be found to provide a license

Cause

On the Microsoft Windows Server RDS infrastructure, there is an issue with the terminal license server.

Resolution

Source: Activate the Remote Desktop Services license server | Microsoft Docs

Activate the license server

1. Open the Remote Desktop Licensing Manager: click Start > Administrative Tools > Remote Desktop Services > Remote Desktop Licensing Manager.
2. Right-click the license server, and then click Activate Server.

Some organizations have a group policy where the license server is explicitly defined.
In such cases:

1. On the RDS host, open the Local Group Policy editor.
2. Navigate to Administrative Templates > Windows Components > Remote Desktop Services > Remote Desktop Session Host > Licensing.
3. Verify Use the specified Remote Desktop license servers and check if the correct server is specified.