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by lunarg on June 5th 2015, at 14:53

A note of caution: when installing the Fortinet SSO Agent on a server, the option to secure connections from a FortiGate with a password is enabled by default, and a random password is assigned.

You have to turn off or change the password before you add the SSO agent in your Fortigate.

There's no mention of this in the manuals, so now you know...