Web.config is being renamed by msbuild

Question

I am using VS 2013 to build a webservice. When it is built, the Web.config file is being renamed "{projectname}.dll.config".

There is a step, _CopyAppConfigFile where it gets renamed, showing in the Output window. I can work around this, by setting the web.config to be copied always, this results in two files, web.config and x.dll.config, which I can live with, but I'd like to avoid it completely if anyone knows how.

EDIT: Looks like this is a result of a MSBuild file, located at:

C:\Program Files\MSBuild\12.0\bin\Microsoft.Common.CurrentVersion.targets

Answer 1

I can recreate this in a default install of Visual Studio 2013 in a C# ASP.NET MVC project. I noticed it because I am starting to transition to Visual Studio 2013, but our build server is still on Visual Studio 2012; our setup project was failing after one of my commits because the superfluous config file that I had harvested on my machine was not being generated on the build server.

This appears to be a discrepancy between the way things worked in the previous version of MSBuild 4.0 / Visual Studio 2012 and the new version MSBuild 12.0 / Visual Studio 2013.

In Visual Studio 2013, the $(ProjectConfigFileName) property is initialized to Web.config [1], which is copied to $(AppConfig) [2], which causes _CopyAppConfigFile to run [3], resulting in an unnecessary config file being named and copied over to the bin directory.

In Visual Studio 2012, the process is similar, except that its version of Microsoft.WebApplication.targets is missing this part that's in the 2013 version:

  <!-- Instruct ResolveAssemblyReferences in MS.Common.targets to generate suggested binding redirects. -->
  <PropertyGroup>
        <AutoUnifyAssemblyReferences>false</AutoUnifyAssemblyReferences>
        <AppConfig Condition="'$(AppConfig)' == '' And Exists('$(ProjectConfigFileName)')">$(ProjectConfigFileName)</AppConfig>
  </PropertyGroup>

The key is that AppConfig line. Since that AppConfig reference is missing in the 2012 version, then _CopyAppConfigFile doesn't run under Visual Studio 2012, resulting in the intended behavior (i.e., the file is not copied).

In Visual Studio 2013, it looks like they added this line so that the build process could offer to fix up binding redirects for you by double-clicking on them in the Errors list in Visual Studio. When Microsoft added this, it seems no one noticed that it resulted in an extra config file being generated and copied to the output folder. So it seems to me as if it is a bug (but a mostly harmless one, since the config file is superfluous) in the new build process in Visual Studio 2013. Since it was conflicting with the Visual Studio 2012 build process on my build server, I added an extra post-build step to blow away the extraneous file:

  <Target Name="AfterBuild">
        <Delete ContinueOnError="true" Files="$(TargetPath).config" />
  </Target>

And then you can feel better knowing that it's not a problem with your particular project or system setup, it's just the way Visual Studio 2013 does things now.

---

File locations referenced above:

[1] C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v12.0\Web\Microsoft.Web.Publishing.targets

[2] C:\Program Files (x86)\MSBuild\Microsoft\VisualStudio\v12.0\WebApplications\Microsoft.WebApplication.targets

[3] C:\Program Files (x86)\MSBuild\12.0\Bin\Microsoft.Common.CurrentVersion.targets