VPN SSL (-455) permission denied error

[jase888]

Setup a Fortigate 60E with the SSL-VPN and it works fine for most users but one user is having a permission denied (-455) error which I cannot work out what is wrong. The password is correct, 2FA code on Forticlient has been setup correctly (twice now to confirm).   It was working yesterday fine but the user tested today and it has this issue. I tried logging in with a different user on that device and it works so its user related but cannot work out what it is.   The logs show little info other than SSL VPN exit error so looking for opinions?

[Toshi_Esumi]

I would look at the authentication server if something for this user got changed.

[neccehh]

I had the same issue and came to the discovery that the version of the FortiClient VPN was the issue. Once updated to a newer version it worked like a charm.