“GatherAllFilesToPublish” Error in VS2010 Project Upgraded to VS2012

PROBLEM: After upgrading a VS2010 web forms project to VS2012, when I went to publish the project I received this error "The target "GatherAllFilesToPublish" does not exist in the project.".

SOLUTION: For me I simply unloaded the project, edited the project file to change this line:

<Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v10.0\WebApplications\Microsoft.WebApplication.targets" Condition="false" />

to this:

<Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v11.0\WebApplications\Microsoft.WebApplication.targets" Condition="false" />

After saving and reloading the project file the upgrade wizard automagically kicked in and did some magic and the publish started working.  

Aftewards I went in and had a look at the project file again and it seemed the upgrade wizard added a PropertyGroup element with VisualStudioVersion and VSToolsParth sub-elements (similar to what this guy recommended manually adding but for me manually adding them didn't work - <Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v10.0\WebApplications\Microsoft.WebApplication.targets" Condition="false" />)

You'll also find lots of links about renaming Microsoft.WebApplication.targets and running a repair (http://stackoverflow.com/questions/10989051/why-do-i-get-the-error-the-target-gatherallfilestopublish-does-not-exist) - which I tried but this didn't fix the issue.