Having successfully installed Studio Enterprise Edition 6.0 and Visual Studio, this particular error has been encountered when creating a solution within a project in Visual Studio. The error message is thrown by the license manager service.

Normally, such errors are encountered having installed time-limited licenses on virtual machine accessed via Terminal Services or Remote Desktop.  In such cases you should contact your SupportLine representative a request a new authorization code for a full license with a drop-dead date.

If the license is not time-limited, rather a full license, then restarting the license manager service should resolve the problem. To do this, simply go to Services and restart the Sentinel license manager service.