The Citrix Licensing service is not running, properly installed, registered on the machine, or the service permissions are not set correctly. The System Event Log may have traces of service-related issues.

To resolve this issue:
1. Launch the Windows Services console: Click **Start** and then type **Services**. 
2. Verify the Citrix Licensing Service is present, restart the service, and check the Event Log for any errors: From the Services console, right-click the Citrix Licensing Service and select **Restart**.

3. Verify the service's Startup Type is set to **Automatic**. If not, right-click the service, select **Properties**, and then, in **Startup type**, select **Automatic**. 
4. Verify that the service is configured to run under the Local Service account.

For more information, see License Administration in the product documentation