Troubleshooting Tip: Explicit Proxy GUI has been disabled automatically after rebooting FortiGate unit or upgrading FortiGate firmware version.

1. This issue may occur when setting gui-explicit-proxy to 'enable' via a CLI command or when enabling Explicit Proxy via the GUI of a FortiGate unit, as shown below. 

1. CLI command:

config system settings

    set gui-proxy-inspection enable

    set gui-explicit-proxy enable

end

2. In the GUI of FortiGate: Under FortiGate -> System -> Feature Visibility -> Security Features -> Explicit Proxy -> Tick to enable it -> Apply.

2. When rebooting a FortiGate unit or upgrading a FortiGate firmware version, the 'gui-explicit-proxy' setting has been disabled automatically, or Explicit Proxy via the GUI of FortiGate has been disabled automatically.

To fix this:

1. For a workaround for a temporary fix:

1. Enable gui-explicit-proxy via a CLI command.

config system settings

    set gui-explicit-proxy enable

end

2. Enable Explicit Proxy via the GUI under FortiGate -> System -> Feature Visibility -> Security Features -> Explicit Proxy -> Tick to enable it -> Apply.

2. For a permanent fix, upgrade the FortiGate firmware version to be 7.4.5 and above.