When I run my program in debug mode, it runs nicely. Now that I want to upload it to the Windows Phone Store, it creates the App Package, but when running the Windows App Certification Kit, it returns the following error:
General metadata correctness test - failed
with the reason:
In the Winmd-File "myBackgroundPart.winmd" (that's my RunTime Component) there is missing "WindowsRuntime 1.3" or "WindowsRuntime 1.2" in the versionstring. The versionstring of the file is "WindowsRuntime 1.4;CLR v4.0.30319".
My environment is Visual Studio 2015 CTP5. The error message suggests, that my WinRT is too new for Store!? How do I downgrade it then?
Edit
This was an issue with VS2015 CTP5, with the new released CTP6 yesterday it was solved.
You need to build your app using Visual Studio 2013 (Update 4 is the latest). Note that Visual Studio 2015 does not have a "go live" license, meaning you can't use it for production purposes anyway. You need to wait until it is released.
Also, when you built the component, what Project Type did you choose? If you built a project for Windows 8.x then I don't think it should have used version 1.4 metadata. Did you build / test on Windows 10 Preview by any chance?