Hold Shift While Dragging To Windows 7 Taskbar To Open Files

Whenever you drag a file to an icon on the Windows 7 taskbar, you are prompted to “Pin” to the taskbar button—but what if you want to open the file instead?

All you have to do is hold down the Shift key while dragging a file to an icon on the taskbar, and the tooltip will change to say “Open with” instead of pinning to the taskbar. If the application was already open, you could always just drag the item to the button, wait for the preview window, and then drop the file onto the open application, but it’s much simpler to use the Shift-drag trick instead.

How to Drag Files to the Taskbar to Open Them in Windows 7 [How-To Geek]