ikev2 remote vpn cannot connect to ZyXEl 200H recently

Hoongks

Hi, I was able to connect to the ZyXEl 200H via windows 11 vpn client using ikev2 vpn until this week. Out of the 10 computers using ikev2 vpn to connect remotely, only 3 computers are having similar problem. It connected and after a few second it disconnects. Now I cannot connect at all after I try resetting my vpn connected. One of the have a different type of error, indicating that there is a firewall blocking the connection. Before that it was working normally. Anyone have similar problem.

PeterUK

If the other PC's connect fine then it must be fine

I take it these PC are remote? what router do they have and have they rebooted?

its possible the Certificate got removed? delete VPN and set it up again