Teamviewer Firewall - Whitelist

You’ve checked the internet. The remote computer is powered on. TeamViewer is running. So, what gives?

Few things are more frustrating in IT support than the dreaded "Connection failed. Partner did not connect to the router." error message. teamviewer firewall whitelist

Here is exactly how to configure your "TeamViewer Firewall Whitelist" to ensure flawless remote connections. Many guides tell you to just open port 5938. That works for home users, but in an enterprise environment, you need whitelisting . You’ve checked the internet

In 90% of cases, the culprit is a strict firewall. So, what gives

Whitelisting means telling your firewall: "Do not inspect, block, or question traffic coming from TeamViewer’s official servers. Let it pass immediately."

| Protocol | Port(s) | Destination | Purpose | | :--- | :--- | :--- | :--- | | TCP | 443 | *.teamviewer.com | Web login & authentication | | TCP | 5938 | *.teamviewer.com | Primary data channel | | TCP | 80 & 443 | master.teamviewer.com | Fallback & master routing |

If you run a corporate network, use a hardware firewall (like SonicWall or Fortinet), or have aggressive antivirus software, you need to whitelist TeamViewer. You cannot simply rely on UPnP (Universal Plug and Play) or hope the traffic slips through.