No implementation file was provicded for the .winmd file

Question

I have a warning when I build my Windows 8 App project in VS2012:

No implementation file was provided for the .winmd file 'C:\Users\luke\LApp\LApp\bin\x86\Debug\Bing.Maps.winmd'. To generate registration information in the app manifest, specify the 'Implementation' metadata on the .winmd reference item in the project file.

I don't really know what other information to provide. I've Googled and it doesn't provide any relevant results. It gives a link to this: http://msdn.microsoft.com/en-us/library/hh708954.aspx but I'm not sure it is the correct thing. I'm pretty sure I have the correct references:

It is a C# project. I used NuGet to add the Bing Maps SDK and it works in my app - I can drag on a map interface and use it in the app. This is just a warning that shows up when building and I have no idea how to get rid of it.

Any help appreciated, thanks.

Answer 1

Is your project a c# project?

Usually WinRT components implemented using .NET are just .winmd files. Both interface and implementation are contained within the .winmd file. Whereas native components (those written in C++) will have separate .winmd and .dll files for interface and implementation respectively.

It would be helpful if you could provide more details about your app project and the repro steps.