Technical Tip: Unable to login to the FortiAuthenticator from GUI

This article describes how to fix the FortiAuthenticator error: 'Please enter correct credentials.

'Note that password is case-sensitive'. Authentication is working fine and the admin user can log in from CLI.

Log in to CLI and apply the following command:

diagnose web restart

This command will restart the FortiAuthenticator web services.

Alternatively, verify if the HTTP-gui and HTTPS-GUI are enabled from the SSH/CLI:

config system interface
    edit port1
        set ip x.x.x.x/y.y.y.y
        set allowaccess ssh http-gui https-gui
    next

Verify that all hosts/domain names are permitted over system-global:

      config system global
         set admin-maintainer enabled
         set timezone 26
         set allowed-hosts *
         set device-fqdn .......

For High Availability:

config system ha

    set mgmt-ip x.x.x.x/y.y.y.y

    set mgmt-access http-gui https-gui

end

Log in to the FortiAuthenticator using 'https://<FortiAuthenticator IP>'.

Verify if traffic is coming into the HTTPS-enabled interface: SSH or console to FortiAuthenticator, then run:

execute tcpdump -i <portX> host <FortiAuthenticator interface ip> and port 443

If it is still not possible to log in from GUI, try to Troubleshooting Tip: Download Debug Report Summary from FortiAuthenticator via GUI or via CLI with TFTP/FTP  (only for v6.3.0 and above) and open a support case.

As for the reason for this issue, make sure to fulfill the RAM/memory requirements:
FAC private cloud 6.6.0 VMWare System requirements as well as following the Technical Tip: Best practices on hardening FortiAuthenticator environments

The FortiAuthenticator web server might have crashed due to a large number of login attempts and a lack of memory.