Is recommended to log this blocked packages. The best way to block it is to add an IP range: for example for teamviewer are: 178.77.120.0/24. If you use a hostname for example Opens a new window some time the FW resolve this dns to the first IP of the dns server response, so if the domain respond with like 10 ips, will just block the first. And in some scenarios there is also mac clients. You need to go computer by computer installing it. Sometimes your Antivirus may block the remote connection, Disable the antivirus temporarily and check for the issue, If you are using windows defender antivirus, Temporarily disable it and troubleshoot your issue.The blocking app are complicated solution. Solution 4: Disable Antivirus once and check Now search for TeamViewer service, Restart the TeamViewer Service once.

Open Run command by pressing Windows + R and type Services.msc this will open the service management console. Solution 3: Restart the Windows team viewer Service Now search for TeamViewer Remote control application and TeamViewer Remote Control Service.Ĭheck and allow both the apps, click on Ok. Open the control panel and Click on Windows Firewall, Now click on Allow an app or feature through Windows Defender Firewall. Solution 2: Allow TeamViewer app in the Windows Firewall settings Ipconfig/flushdns ipconfig flushdns will clear all the stored DNS resolver cache. Ipconfig/renew ipconfig renew will assign new ip from DHCP

Ipconfig/release ipconfig release will release the ip address from the system Open Run command by pressing Windows + R and type cmd hit enter, This command will open the command prompt.

Solution 1: Flush DNS to fix Protocol negotiation failed Solution 4: Disable Antivirus once and check.Solution 3: Restart the Windows team viewer Service.Solution 2: Allow TeamViewer app in the Windows Firewall settings.Solution 1: Flush DNS to fix Protocol negotiation failed.

Allow teamviewer through firewall