Automatic Protection Turns Itself Off

About a month ago I found Automatic Protection turned off on my wife's Mac. She said she didn't know how it happened.

I had to turn it back on using my wife's laptop password. So I am confident she had not done it,  because she didn't know how to turn it on or off.

Today, I was performing a Quick Scan on my Mac and after it completed, while still on the page, I saw the Automatic Protection go from green to red (indicating an off condition).

I did nothing to do this!  I am aware that  to turn it on or off, requires my computer password to be entered so I knew  that I had not turned it off.

I find this to be a serious problem that can open my computer to any virus infection. Has anyone witnessed this problem? I did find reference to this from a 2004 security bulletin.

I assumed that this problem had been fixed. This may be a new problem with Norton but I can find no reference to anyone's comments concerning it.