There may be instances in which application windows end up being placed beyond the viewable area of the screen.
Apple Discussions poster astronoman writes:
"So some programmer made a major booboo and now the iTunes equalizer is outside the viewable area of my screen -- I can see it just fine with Expose. How in the world can I move the window back to where I can see it?"
Mac OS X is built so that users cannot manually move windows beyond the confines of the screen. The furthest users can move a window off the screen is enough so that, at the very least, a single pixel of the window's frame is available to view. Additionally, windows should not be able to move a window toolbar no further up than the bottom edge of the system menubar, and no further down than the bottom of the screen. If users place a window so that the toolbar is cut off by the bottom of the screen, OS X should readjust the window so the toolbar is visible. Despite this design, however, poor programming or other issues could result in windows being placed outside the viewable screen area, or at least appear to be placed off the screen.
The following suggestions may help users center such windows.
Adjust monitor settings and double-check edges While many displays use digital connections which automatically align the image to the available space of the display, this is not the case with analog connections. If users are connecting their displays through a VGA connector, it is possible that their display image's width, height, horizontal or vertical positioning may be slightly off, resulting in the last few pixels being cut off. If this is the case and a window is placed along the cropped edge, the window will appear to have disappeared. Here is an example of a window placed at the bottom edge of the screen, with only a sliver of the window being visible that could easily get cut off if the display settings are slightly off.
As such, it is recommended to adjust these display settings to see if the lost window is visible along one of the edges.
Change the display resolution If the screen is not displaying at its "native" resolution, it is possible that increasing the resolution will reveal the missing window. Additionally, if the resolution is at the maximum possible for the display, users might try reducing the resolution by one or two settings. In the new resolution, quit and relaunch the problematic application and then change the resolution back to the full settings, which might reset the window positioning on the screen.
Hide the dock While Mac OS X should keep windows from being placed behind the dock, sometimes windows can wind up hidden behind the dock anyway, which can prevent users from selecting the window. As such, the only way to get access to the window would be to hide the dock and check the area under the dock.
Activate Expose and Spaces Since users affected with this problem can see the window when Exposé is activated, users can attempt to make the window viewable by using a combination of expose and spaces. With the problematic application window open, activate both expose and spaces at once, and then drag the window to a new space. Upon deactivating expose and spaces, go to the space containing the window, and drag it back to the original space if it is showing there.
Delete appropriate preferences files Many window settings are stored in application preferences. As such, users can try removing the preferences files for the application that is experiencing this problem. Preference files are usually stored in the /username/Library/Preferences/ folder and should be named by a convention such as topleveldomain.company.program.plist, such as com.apple.iTunes.plist for iTunes.