When you open a program or folder window, it may look like it has minimized to the taskbar but the window doesn’t appear when clicked on the Taskbar icon. Or the program window may show up partially off the screen.
This happens if you had extended the display to second monitor earlier, moved the program windows there and forgot to switch back to single monitor setting. When you move a folder or program window to the extended display and then close the window, the window position (x,y) is saved (by most applications). So later on you forget to switch on the 2nd monitor and don’t realize that your programs are showing up there.
For example, Notepad updates its last window position in the registry:
Erasing those registry settings would cause Notepad to show up in primary display. In the case of applications that don’t store the last window position, they default to the primary display when opened. I verified it with a small program I wrote which doesn’t save window settings. So it’s a per-application window position thing, rather than the Operating System remembering the program window and screen position.
The quickest way to show all open program windows in your primary display is to press WinKey + P and choose PC screen only. If you’re not extending the display, but using only the second monitor which is the case of many laptop users, select Second screen only.
That brings back all the windows to the viewport of your primary display where ever they were before. This also applies to desktop icons which were earlier moved to the 2nd or extended display.
About the author
Ramesh Srinivasan founded Winhelponline.com back in 2005. He is passionate about Microsoft technologies and has a vast experience in the ITeS industry — delivering support for Microsoft's consumer products. He has been a Microsoft MVP [2003 to 2012] who contributes to various Windows support forums.