Problem Symptom
The detailed error message is as below:
RemoteApp Disconnected
Your computer can’t connect to the remote computer because the Remote Desktop Gateway server address is unreachable or incorrect. Type a valid Remote Desktop Gateway server address.
RemoteApp Disconnected
Your computer can’t connect to the remote computer because the Remote Desktop Gateway server is temporarily unavailable. Try reconnecting later or contact your network administrator for assistance.
Follow the below solution steps to resolve RemoteApp Disconnected error because Gateway server is temporarily unavailable or address is unreachable or incorrect.
Solution
The machine trying to connect needs to be able to resolve the public name of the Remote Desktop Gateway server. And this may NOT be the hostname of the server. You need to set the public name of the Remote Desktop Gateway server in the servers IIS Settings.
Go to the Gateway server: Start > Administrative Tools > Internet Information Services (IIS) Manager > {Server-name} > Sites > Default Website > RDWeb > Pages > Application Settings > Set DefaultTSGateway to the public name of the gateway server.
Execute the command iisreset to restart the web services.