You manage a server named Server2 that runs Windows Server 2008 R2.
You install and test the Remote Desktop Services server role on Server2.
You publish an application by using Remote Desktop Services.
All users must connect to the Remote Desktop Services application by using the Remote Desktop Protocol.
You install and configure the RD Gateway role service on Server2.
You configure a default domain policy to enable the Enable Connection through RD Gateway setting.
Users report that they cannot connect to the Remote Desktop Services application.
You need to ensure that users can access the Remote Desktop Services application on the intranet and from the Internet.
What should you do?

A.
Configure the Enable Connection through RD Gateway Group Policy setting to Disabled.

B.
Configure the Set RD Gateway server address Group Policy and configure the IP address of the RD Gateway server. Link the Group Policy object (GPO) to the domain.

C.
Configure Server Authentication on the Remote Desktop Connection client to Always connect, even if server authentication fails for all users.

D.
Enable the Set RD Gateway server authentication method Group Policy to the Ask for credential, use NTLM protocol setting. Link the Group Policy object (GPO) to the domain.

Explanation:
How to use the Group Policy Management Console (GPMC) to enable connections through RD Gateway. When this policy setting is enabled, when Remote Desktop Services clients cannot connect directly to an internal network resource (computer), the clients will attempt to connect to the computer through the RD Gateway server that is specified in the Set RD Gateway server address policy setting.
Source: http://technet.microsoft.com/en-us/library/cc726011.aspx