https://www.dotnetzone.gr:443/cs/blogs/birbilis/archive/2013/02/10/fix-visual-studio-opens-class-diagram-in-xml-editor-with-double-click.aspxRecently, to save myself sometime after having renamed some interfaces/classes in the ClipFlair project sourcecode, I right-clicked one of the class diagrams (.cd files) in it at Visual Studio’s “Solution Navigator” (this is an enhanced Solution ExplorerelCommunityServer 2.1 SP3 (Build: 20423.1)