The Attachments Pane gives you a centralized place to see and organize and save file attachments in a PDF document.
It lets you view, insert, delete and export any files that are attached to your PDF file.
This pane is a content-aware element, and its tab is visible in the side-bar only if the PDF document contains attachments.
In the sidebar, click the Attachments tab to toggle visibility of the Attachments pane
In the Attachments Pane, click on an attachment to select it, and do one of the following:
NOTE: You can select many attachments by holding the Ctrl key as you click on different items.