Sometimes after installation you have user interface grayed out. In order to enable user interface so you can disable or enable McAfee Virusscan, you have to make sure that you have administrative rights and full access to the registry. Sometimes if you reboot computer in safe mode it will work as well. In order to reboot computer in safe mode, during booting just hit “F8” and you will see selections list from which you can select “Safe Mode” to boot the computer in. Make sure you do a full registry backup first.
From the command line in “run” field type in: regedit.
Then go to HKEY_LOCAL_MACHINE\SOFTWARE\McAfee\DesktopProtection and change UIPMode to 0 and UIP to empty string.
[HKEY_LOCAL_MACHINE\SOFTWARE\McAfee\DesktopProtection] "UIPMode"=dword:00000000 "UIP"=""
Then delete the following policies for ePolicy Orchestrator (you may need to do:
HKEY_LOCAL_MACHINE\SOFTWARE\McAfee\ePolicy Orchestrator\Application Plugins\VIRUSCAN8600 HKEY_LOCAL_MACHINE\SOFTWARE\Network Associates\ePolicy Orchestrator\Application Plugins\VIRUSCAN8800
Sometimes you wil have different options available on different Microsoft OS. But you get the idea on how to unlock the user interface.