I have windows 8 x64 that came preloaded with trial McAfee. Uninstalled after trial and security screens inform Defender turned off. Selecting to turn off does not configure the change. What is easiest way to fix issue and "move on" ?

Run regedit.exe, go to

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Defender

and change the values from DisableAntiSpyware and DisableAntiVirus to 1.

is there a more user friendly answer?  certainly MS wouldn't expect all users to be comfortable with this answer.  Is there no other way to turn it back on?  I am disappointed at how often changing registries is the answer to something that should be as easy as clicking boxes or changing settings.