Technical Note: FortiClient SSL VPN connection status gets stuck at 40%

[achowdhury]

Description

This article provides a possible solution for the SSL VPN connection attempt stopping at a status of 40% with the warning message "Unable to establish the VPN connection.  The VPN server may be unreachable. (-5)".

Solution

Check in the internet explorer settings under Internet Options > Advanced >  that TLS 1.0, TLS 1.1
and TLS 1.2 have been set to enable.

If they are not enabled, enable them and verify the connection.