Attaching Files to a Forum
From the forum that is being posted or replied to click on "Add..."
From the "File Picker" click on "Upload a file" and then click on "Browse"
Locate the file from the computer, left pane will list the locations (Flash drive / Computer/ Documents) in the right pane is the folders to search for the document. Select the file and click on open.
Click on "Upload this file", this will return to the discussion forum page.
The file is now attached and viewable from here, to finish the posting click on "Post to forum".