Step 1 - Find location of VirtualMate.exe on your computer. Copy the location.

Step 2 - Go to System Settings 'Allow a program / app through Windows Firewall.'

Windows 7

Choose Start→Control Panel→System and Security→Allow a Program through Windows Firewall.

Windows 10 

Choose Start→Settings→Search: allow an app through windows firewall.

Step 3 - Add VirtualMate.exe to the allowed list.

Add another program / app → Browse → Paste the VirtualMate.exe location into the location bar → Select VirtualMate.exe