The RD Gateway service could not be initialized. The following error occurred: "%2". To diagnose possible causes for this ...

The RD Gateway service could not be initialized. The following error occurred: "%2". To diagnose possible causes for this problem, verify whether the following services are installed and started: (1) World Wide Web Publishing Service (2) Internet Authentication Service (IAS) (3) RPC/HTTP Load Balancing Service. Also, check Event Viewer for Network Policy Server (NPS) and IIS events that might indicate problems with NPS or IIS.