I have a Visual Studio 2013 solution that is under source control (TFS, Visual Studio Online). It is mapped to a local workspace, I have checked out some files (e.g. web.config,
I had the same issue and created a bug on Connect. Let's hope this gets fixed
https://connect.microsoft.com/VisualStudio/feedback/details/860265/unable-to-save-files-in-vs-2013-update-2-rc2