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The file will open in the Viewer page.
The currently selected file is always highlighted
Drawings 
The Drawings button will return you to whichever drawing page you were last on.
If you click the Inbox folder on the Documents page you will be taken to the Inbox page.
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The Inbox page list all of the files you have opened and uploaded from your email sources.
Drawings
Edit List
The Edit List button allows to edit the file list.
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