Windows L2TP VPN Clients

I have a couple of customers whose L2TP-IPSEC VPN Windows 10 client connections stopped connecting to the company VPN.
To fix this:
  1. Uninstall all the WAN Miniport devices, under Network Adapters, in Windows Device Manager.
  2. Then Scan for Hardware Changes and let Windows reinstall the WAN Miniport devices.
  3. Then try your L2TP WPN Client. It's bound to work!