Dec 15, 2013 03:40 AM|Angie xu - MSFT|LINK
To my regret, this information is insufficient to give you a precise answer why this happens.
As we know, Visual Studio has backward compatibility, when you want to move to Visual Studio 2013, you can follow this document to find out which solutions, projects, files, and other assets that you created in Visual Studio 2012 or Visual Studio 2010 SP1
will run without modification in Visual Studio 2013.
# Visual Studio 2013 Compatibility: