My Mac won't load the Users & Groups preference pane: Fix
I had recently had a Mac on Lion unable to load the Users & Groups Preference Pane. Like this: My IT support had suggested reimaging the computer. Reinstalling the Operating System, reloading the applications, and transferring back the User information from Time Machine Backup. Well, after doing all of that, the problem reappeared immediately. I scoured through Apple Support Communities and found this fix. For some reason, some transparent users are showing up in your system. They need to be deleted. But since you cannot load Users & Groups... it becomes a problem. Here is the solution / procedure. Quit System Preferences. Launch Terminal. (Applications/Utilities/Terminal) Copy & Paste these commands. sudo dscl . delete /Users/Guest press enter Terminal may ask for your Administrator Password, enter that. sudo dscl . delete /Users/Guest1 press enter Terminal may ask for your Administrator Password, enter that. Rel