Q: What Windows Firewall ports does Citrix XenDesktop use to communicate with its VMs?

For core functionality, enable ports for ICA, Workstation Agent, and CGP services: TCP ports 1494, 80, and 2598.

For user-to-user desktop shadowing, enable ports for Remote Assistance: TCP port 3389.

For real-time monitoring, enable the Remote Management feature.

For HDX RealTime for Audio, open UDP ports 16500 through 16509.