This tutorial will show you how to pin a program or file to the Windows 7 taskbar.
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This is how the Windows 7 Taskbar looks like for reference
Drag a item you want to pin to an empty space of the taskbar until you see the Create link in Taskbar tool tip and drop it as shown below.
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Another way to do this is to move the cursor over a taskbar button, of which is open. Click the arrow to the right of the icon and select Pin this program to the Taskbar.