Has a keyboard shortcut ever changed the monitor's display colors or caused other unexpected changes on the display? These changes are often the result of changes to the settings in the Universal Access pane of System Preferences, which include:
- The White on Black option being set causing the colors on the screen to be inverted.
- Having the VoiceOver option turned on, which results in icons having black boxes and some of the menu items in the Apple menu being duplicated.
- The screen contrast being set very high, which can cause the display to look solarized.
In these cases, the setting can be turned off by clicking on the System Preferences icon in the Dock, clicking on Universal Access, and correcting the setting.