I am using Windows 10 with the latest update. I have just installed McAfee AntiVirus (version number: 16.0; release name: 16.0 R34). I noticed that when a update check completed, I got a notification from Windows Security Center saying that McAfee is snoozed (see screenshot below)
I checked the Task Manager and noticed that the McAfee process was not terminated and seemed to be running normally (see the screenshot below). So McAfee might not have been turned off.
I then opened Windows Security Center and found that both Windows Defender and McAfee were shown to be in a closed status (see the screenshot below).
I think it might be a bug and a fix is needed.