[CentOS] Lost my menu options again - KDE messes with Gnome?

Okay, I finally figured out what the problem was in making a new user.
Turns out that I can only log in with the newly created user account
after having rebooted. I would have thought it would have been good
enough to just log out and log back in, but apparently not.

Anyway, now I can get back on track to the original point of this
thread.

I logged into the new account and the missing "Preferences" menu item
was not there either. So whatever has changed to remove it from my menu
has happened globally to all users.

So if it's not just a user settings issue, then what could it be?

Dave