To unblock TeamViewer from the Windows Firewall, click Start, Control Panel, Security Center, and then select Windows Firewall. You can fix this by allowing the program to pass through the Windows Firewall by adding it to the exceptions list.
Here, it is possible that Microsoft Windows is blocking TeamViewer from accessing the internet. You normally get this problem when the program is being blocked by the operating system.
Since “No connection to Master Server” is displayed on top the dialog box and the message says “Please check your internet connection”, this means the TeamViewer application cannot establish a connection to the internet. TeamViewer is not connecting to Master Server, how can i do?
