I use Symantec Endpoint Protection as AV in my environment. It should automatically disable Windows Defender Antivirus but it did not. Nessus started flagging since I do not update the Windows Defender AV signature definition which is required to be updated every day.

Found this reference at Nessus site Potential False Positive for plugin 103569 (tenable.com) I went to disable in the registry but it didn’t allow me to modify the registry. I use GPO – Computer Configuration->Administrative Template->Windows Component->Windows Defender Antivirus-Turnoff Windows Defender Antivirus