First, go to Start > Control Panel > System and Security > Windows Firewall > Allow a program through Windows Firewall and click Allow another program button. Use the Browse option to navigate to X-lite installation directory, select its executable file and press Add. After that, go to Windows Firewall, press Advanced Settings and select Inbound Rules. Click New Rule from the right, check the Port box, click Next, select All local ports and then Next again. Check the Allow the connection box, press Next twice and follow the instructions. Also, make sure that your antivirus program doesn't block the connection with its Firewall. If the problem is not solved, download and install the latest version of the program and configure it using the user guide provided by CounterPath Corporation.