Once in a blue moon you may experience an OS X lockup and non-responsive computer. Granted, I can't remember the last time I had a lockup on my MAC. I am sure I have just can't recall since its so rare an occasion.
However, since upgrading to OSX MS OFFICE 2008 and using EXCEL I have experienced lock ups so regularly I sware I'm on Windows.
The first thing you should try is to quite the abusive application through the FORCE-QUIT facility from the Apple menu. I found myself not having the ability to click the Apple Menu as the Rainbow Wheel of Death was churning happily along and ignoring all mouse click requests.
Rescued by a few through keystrokes I thought it better to document it and share important last resort keystrokes for easy reference.
Command(apple)-Option-ESC to initiate the force quit menu
Command-CTRL-Power to reboot the computer (this is analogous to Control-OpenApple-Reset for Apple ][gs Users)
Command-Opt-Shift-Power : This shuts down the computer (Is closest to WINDOW CTL-ALT-DELETE)
Control-EJECT initiates the shut down dialog
Hope this is helpful.
tags: ctlaltdelete osx reboot forcequit
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