Was there any other client vpn software used before Meraki Client VPN? I have had similar issues with computers that transitioned from Forticlient to Meraki.
IKE and AuthIP IPsec Keying Modules disabled (Windows only) Solution: This occurs most often when 3rd party VPN software has been installed and disables the IKEEXT service. This can be re-enabled by navigating in Windows to Control Panel > Administrative Tools > Services. Find the service named "IKE and AuthIP IPsec Keying Modules" and open it. Change the Startup type to "Automatic". If this automatically reverts to "Disabled" or fails to start, it may be necessary to remove the 3rd party VPN software:
I realise that this thread is very old and that there are loads of methods out there to resolve this, but yesterday on two machines i have i was having nothing but issues, all error 809.
Long story short, Disabled Xbox Live Networking Services, and 100% working without any other intervention.
If you search for generic Windows 10 809, and exclude "meraki" from your search, there are a few troubleshooting guides with the same level of items we have here (uninstalling WAN Miniports etc) but i demonstrated on my home PC and my work laptop that stopping the Xbox Live Networking Services had the immediate result of allowing my Meraki VPN to connect.