How do I get rid of a menu extra that I installed? I am on a limited functionality school account with no access to System Preferences. I am a curious child, and I opened the folder Mac HD -> System  -> Library -> CoreServices ->Menus. I copied all the .menu files to my desktop and opened a few of them. I now want to get rid of the menus from the notification area. I can move the .menu files to the trash, but I can't delete any of them that I already opened. I get a "File in Use" error. Any help would be greatly appreciated.
Command &#x2318;-drag them off your menu bar, then you should be able to trash them.  You might also want to log out and log back in.