Как сканировать VPN с помощью Nmap

У меня Zenmap установлен на моей машине Windows. Как сканировать VPN-сеть? Команда, которую я использую:

nmap -T4 -A -v 192.168.0.1-255

но он выходит с ошибкой:

WARNING: Using raw sockets because ppp0 is not an ethernet device. This probably won't work on Windows.

pcap_open_live(ppp0, 100, 0, 2) FAILED. Reported error: Error opening adapter: The system cannot find the device specified. (20).  Will wait 5 seconds then retry.

pcap_open_live(ppp0, 100, 0, 2) FAILED. Reported error: Error opening adapter: The system cannot find the device specified. (20).  Will wait 25 seconds then retry.

Call to pcap_open_live(ppp0, 100, 0, 2) failed three times. Reported error: Error opening adapter: The system cannot find the device specified. (20)

QUITTING!