Update 2013-12-02: WiX Toolset 3.8 is released with official support for Visual Studio 2013 editions. It is available for download from wixtoolset.org.
You can manually enable Visual Studio 2013 compatibility with older versions of WiX:
Copy
C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\Extensions\Microsoft\WiX
to
C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\IDE\Extensions\Microsoft\WiX
Modify
C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\IDE\Extensions\Microsoft\WiX\extension.vsixmanifest
by adding the following:<VisualStudio Version="12.0"> <Edition>Ultimate</Edition> <Edition>Premium</Edition> <Edition>Pro</Edition> <Edition>Express_All</Edition> </VisualStudio>
Then open VS2013 Native Tools Command Prompt (from
C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\Tools\Shortcuts
) and execute:devenv /setup
When you open Visual Studio 2013, WiX 3.7 projects will be compatible.