The users of this Addin can display documents of a Document Management System in a TaskPane that can be hidden and showed using a button in the RibbonUI.
When users creating new emails, they can open a dialog and browse for documents and mark them for download and attach to email.
The documents are downloaded locally and attached to the email.

A Taskpane that displays Webcontent of a Document Management System.
Users can select documents and attach them to Messages.