If you must use NetExtender on Windows 8.1, keep the following compatibility details in mind:
The SonicWall NetExtender SSL VPN client was historically a common way to connect Windows 8.1 devices to corporate networks. However, because , it is no longer receiving security updates, making it a significant security risk for VPN connections . Compatibility & Configuration Sonicwall Netextender Windows 8.1
: If you see "Windows Remote Access Service (RAS) has encountered an error," try uninstalling the WAN Miniport (IP) and WAN Miniport (PPTP) devices from the Device Manager and then scanning for hardware changes to reinstall them. If you must use NetExtender on Windows 8