In the Windows explorer, on the left side, you have the navigation pane, in which a sections is Favorites, where you can see places like Desktop, Recent Places, etc. If you wish, you can add a folder or library to this favorites section in Windows explorer.
To do so, browse to the folder which you want added to this section.

Next right click on Favorites in the LHS navigation pane, and and click on Add Location in Browser to Favorites.
Alternatively, you can also use the drag and drop method to do so or re-arrange them.
To know How to Add Network Location & other non-indexed locations to Windows 7 Libraries go here.
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