Block TeamViewer Connections

TL;DR

This guide shows you how to block unwanted incoming TeamViewer connections using Windows Firewall and within the TeamViewer application itself. This prevents people from connecting to your computer without your permission.

Blocking Incoming TeamViewer Connections

1. Check TeamViewer Settings: First, make sure unattended access is disabled if you don’t need it.
   • Open TeamViewer.
   • Go to Extras > Options.
   • Select Security in the left-hand menu.
   • Under ‘Remote Control’, uncheck “Permit incoming remote control connections”. Also, ensure that unattended access is disabled if you don’t require it.
   • Click OK to save your changes.
2. Block TeamViewer via Windows Firewall (Recommended): This provides a more robust block.
   • Open Windows Defender Firewall. You can search for it in the Start Menu.
   • Click Advanced settings on the left-hand side.
   • In the ‘Windows Defender Firewall with Advanced Security’ window, click Inbound Rules on the left.
   • Click New Rule… on the right-hand side.
   • Select Program and click Next.
   • Choose This program path: and browse to the TeamViewer installation directory (usually C:Program FilesTeamViewer) and select TeamViewer.exe. Click Next.
   • Select Block the connection and click Next.
   • Ensure all profiles (Domain, Private, Public) are checked. Click Next.
   • Give the rule a descriptive name like “Block Incoming TeamViewer” and click Finish.
3. Verify the Block: Test to make sure connections are blocked.
   • Ask someone you trust to try connecting to your computer using your TeamViewer ID and password (if unattended access is enabled, disable it first for testing). They should not be able to connect.
   • You can also use a second device on the same network to attempt a connection.

Additional Notes

• TeamViewer Updates: TeamViewer updates might sometimes reset firewall rules. It’s good practice to check your firewall settings after each update.
• Multiple Rules: If you have multiple versions of TeamViewer installed, repeat the firewall rule creation process for each version.
• Outbound Connections: This guide focuses on blocking incoming connections. Blocking outbound connections is generally not recommended as it prevents you from initiating TeamViewer sessions yourself.