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