Global hotkeys (Expos�, Spaces, etc.) suddenly disabled

Several readers have reported an issue where global hotkeys for triggering specific functions in Mac OS X 10.5.x (Leopard) are suddenly disabled. In other words, for instance: F11 is set to reveal the Desktop via Exposé, or F11 is set to activate Spaces, but suddenly the triggers no longer work and only a system alert noise is played when these keys are pressed. Inspecting System Preferences will reveal that, indeed, the settings are no longer in place. The same problem can affect hot corners that are designated for Exposé, and Dashboard functionality.

In some cases, it appears that Blizzard's World of Warcraft may be to blame. The game appears to delete some of the aforementioned settings when quitting or crashing. A post from a Blizzard developer in the company's forum blames Mac OS X:

"Every time we have tried to fix it, we have come away with the assessment that it is an OS bug."

A user in the forums created an AppleScript that will resolve the issue when it occurs. The script should be run after quitting (or crashing) World of Warcraft. As with any unknown script, you should inspect this download carefully before running it.

Other potential cures for this issue:

• Launch Activity Monitor (located in /Applications/Utilities) and look for a process called "ScreenSaverEngine," which may be hung. Quit the process. Go to the Desktop & Screen Saver pane of System Preferences and turn off the Screen Saver.
• Unplug then reconnect your USB keyboard.

Feedback? Late-breakers@macfixit.com.

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