I am trying to edit a UML diagram that was created in Visio 2010 or in an earlier version of Visio by using Microsoft Visio 2013. However, the legacy UML features are missing. Additionally, I receive the following message in the message bar and in the information pane: This UML Model Diagram was created with a feature that is not supported in this version of Visio. Editing of the diagram is limited and may result in the diagram not working in earlier versions of Visio.