Wifi "disabled" by user1 cannot be "enabled" by user2
Reproduce by:
login user1, disable wifi
switch to user2, enable wifi
This problem could be related as well:
Its also multiuser, and I have a feeling this has something to do with the security model.
Navigate to top menu System > Preferences > Internet and Network > Network Connections. In the Network Connections dialog box select your WiFi connection and click properties button with gear sign on it. Select 'General' tab and check 'All users may connect to this network' box.
Thanks for the help, but its already checked.