Before installing XenApp 6.5, he had two components that depend on the environment that he probably wants to configure:
In previous versions of XenApp, he needed to install Remote Desktop Services (formerly known as Terminal Server) before the XenApp setup. In XenApp 6.5 (and 6.0), the setup process will install Remote Desktop Services automatically.
He had multiple options to configure Windows Firewall:
Open Group Policy Management Editor and expand Computer Configuration | Policies | Administrative templates | Network | Network Connections | Windows Firewall | ...