Troubleshooting “Error in Serving the Request” in a Double DMZ UAG Deployment for Horizon Introduction Designing a double DMZ architecture for Omnissa Unified Access Gateway (UAG) is a well-established best practice in highly secure environments. By introducing an additional reverse proxy layer, organizations can further isolate internal Horizon infrastructure while still delivering seamless remote access. However, this added complexity introduces subtle configuration challenges. One of the most common and frustrating errors administrators encounter is: Error in serving the request. This article provides a deep technical explanation of the issue, along with practical remediation steps based on real-world experience. Architecture Overview In a typical double DMZ deployment : External Client │ ▼ UAG #1 (External DMZ – Reverse Proxy) │ ▼ UAG #2 (Internal DMZ – Horizon Edge) ...