‘The VPN server may be unreachable (-14)’ for FortiClient
OpenVPN: No TAP Adapter Available
Solution: Enable the TAP adapter in Windows

The operation returned because the timeout period expired |
Solution
Configure Check Point Capsule VPN to always run in the background:

Go to Settings > Privacy > Background apps > Background Apps “on” and Check Point Capsule VPN set as “on”.

Forticlient issues:
10% – Local Network/PC issue
31% – Certificate not trusted, warning sometimes hidden in background (move window)
40% – Application or the Fortigate causing the error, occasionally caused by the local machines/network setup
45% – MultiFactor Authentication
80% – Username/Password issue ; or trying to connect to wrong port number
98% – Disable ipv6 on both the physical adapter and the virtual adapters
Still not resolved: reinstall the forti-client