I ran into something on machines that have .NET 4.5 installed: (NOTE: This is on an app targeting the 4.0 framework, and the behavior changes when a client machine installs the 4.5 framework, and ...

Basic info: VS2010, .Net 4.0 WPF application. I'm trying to write a dialog box that allows a user to edit a fairly simple configuration file, opened as an XMLDataProvider as an application-level ...