title: project .cs files contain using Microsoft.SharePoint;
body: <p>I am trying to migrate a solution that was used in SharePoint 2007 to SharePoint 2013.  I tested the project in 2010 and it functions there.  It doesn't work in 2013.  I found a number of errors related to .net 3.5 vs. .net 4.5.  How do I change the cs files to accept use in .net 4.5?</p>