Third party antivirus software and realtime protection
For FortiClient in standalone mode, it is recommended to remove third party antivirus products before installing FortiClient or enabling the antivirus realtime protection feature. Otherwise you may see the following conflicting antivirus warning when you enable realtime protection:
In managed mode, when FortiClient Telemetry is connected to FortiGate, the FortiGate compliance rules may allow third party antivirus software to be used as part of the compliance rules. In this case, you should disable realtime protection in FortiClient.