Run: sudo update-rc.d openvpn disable. Then you'll have to run sudo service openvpn start to manually start the VPN.
Or edit the file /etc/default/openvpn sudo gedit /etc/default/openvpn. And uncomment the line: #AUTOSTART="none" So it looks like: AUTOSTART="none"
https://askubuntu.com/questions/302933/how-to-disable-openvpn-from-autostarting-at-boot-up-or-reboot
Or edit the file /etc/default/openvpn sudo gedit /etc/default/openvpn. And uncomment the line: #AUTOSTART="none" So it looks like: AUTOSTART="none"
https://askubuntu.com/questions/302933/how-to-disable-openvpn-from-autostarting-at-boot-up-or-reboot