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articles/network-watcher/vm-network-troubleshooter.md

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+---
+title: VM Network Troubleshooter overview
+titleSuffix: Azure Network Watcher
+description: Learn about VM Network Troubleshooter in Azure Network Watcher how it can help you troubleshoot traffic issues.
+author: halkazwini
+ms.author: halkazwini
+ms.service: azure-network-watcher
+ms.topic: concept-article
+ms.date: 05/07/2025
+---
+
+# VM Network Troubleshooter overview
+
+Blocked ports on their VMS are one of the most common connectivity issues faced by Azure customers. 
+The VM Network Troubleshooter helps customers quickly check if commonly used ports are blocked on a their Azure virtual machine.
+
+## What ports are check by the VM Network Troubleshooter?
+
+The VM Network Troubleshooter checks for the following ports:
+ - Port 80 (HTTP)
+ - Port 443 (HTTPS)
+ - Port 3389 (RDP)
+
+
+## How can customers access the VM Network Troubleshooter? 
+
+Customers can access the VM Network Troubleshooter from the Monitor tab on the VM Overview blade. 
+With a single click, customers can start the troubleshooter and check if RDP, HTTP and HTTPs ports are blocked. 
+
+
+## How does the VM Network Troubleshooter work? 
+
+The VM Network Troubleshooter is built on top of the NSG diagnostics tool. The troubleshooter simulates traffic to the VM for common ports. It returns whether the flow is allowed or denied with detailed information about the security rule allowing or denying the flow.
+Customers can clickthrough from the results to the NSG rules and edit them as needed. 
+
+## Next step
+
+To check for other ports, customers can use the NSG diagnostics tool
+
+> [!div class="nextstepaction"]
+> [NSG Diagnostics overview](nsg-diagnostics-overview.md)