RemoteApp cannot connect to webapp

remoteappwindows-server-2008-r2

I have just set up a Server 2008 R2 machine with Remote Desktop Services. It's all running on the one server, just for a single application, which works fine locally and when using Remote Desktop Web Access on the local network.

However, when accessing it over the Internet, you can log on to RD Web Access fine, but when running the RemoteApp you get the message:

RemoteApp Disconnected
The remote computer could not be found. Please contact your helpdesk about this error.

The application and all Remote Desktop services are on a single machine. I have purchased and installed a GoDaddy Cert. It works like a charm in the local network, but I get the above message when trying to access through rdweb
How can I enable the RemoteApp to function outside the local network? I think there is one or 2 steps I left out??.. Please help…

Best Answer

It sounds like your RemoteApp's .rdp file (or RDweb "source name") may refer to a hostname that can be resolved only on the LAN, or perhaps it refers to an RFC 1918 IP address.

Using an .rdp file:

  1. Open the RemoteApp's .rdp file in Notepad.
  2. Verify that the hostname in the .rdp file is resolvable outside the LAN. For example, at a command prompt, you could type "nslookup hostname.domain 8.8.8.8" to see whether it can be resolved by Google Public DNS.
  3. If the hostname in the RDP file cannot be resolved from the public internet, or if it resolves to an RFC 1918 IP address, use Notepad to substitute the server's FQDN (or public IP address).
  4. In Notepad, choose File -> Save.
  5. Transfer the modified .rdp file to the remote computer and then retry opening the RemoteApp by double-clicking on the .rdp file.

Using RD Web Access:

  1. Logging in as "administrator" on the https://terminalserver/rdweb configuration page.
  2. Make a similar configuration check/change to the RemoteApp Source Name. Again, it must be a fully qualified domain name or routable IP address; if it is a NetBIOS name, it won't work outside the LAN.

[Disclaimers: (1) I have never personally deployed or used RD Web Access. (2) I have never served a RemoteApp to a computer outside my LAN without requiring a VPN connection. The potential security benefits of requiring a VPN connection are beyond the scope of this question, but, in my opinion, they should be considered carefully before allowing any kind of RDP access from outside a trusted local area network.]

Related Topic