You cannot run Windows Phone 8 SDK emulator in Visual Studio 2012 for Windows 8.1 Preview

Article ID: 2864215 - Last Review: June 26, 2013 - Revision: 1.0 Applies to Windows Phone Developer Tools Windows 8.1 Preview Microsoft Visual Studio Express 2012 for Windows 8 Microsoft Visual Studio Express 2012 for Windows Phone Microsoft Visual ...

support.microsoft.com