By default, Windows Explorer always opens with Libraries. If you wish, you can choose another folder.
%SystemRoot%\explorer.exe path
Where path is the path of the folder you want to open by default. Here, for example, we open the folder c:\office:
Some paths are more complex than others:
A video walkthrough is available by clicking here:http://www.mediaforma.com/en/oneminuteaday/windows-7/set-windows-explorer-default-folder.html