The error message (listed below) will occur on store submission if you use Visual Studio 2017 (pre-update 5 version 15.4 or older) to generate the .appxupload file as outlined in the documentation https://docs.microsoft.com/en-us/microsoft-edge/extensions/guides/native-messaging).

"Package acceptance validation error: Apps converted with the Desktop Bridge and that require the .NET Native framework must be pre-compiled by the .NET Native tool chain.”

The workaround listed below will resolve this issue.

1. Generate the package with Visual Studio. This will produce both an .appxupload file and a folder with the _Test suffix.
2. Ignore the .appxupload file produced by Visual Studio 2017 version 15.4.
3. Create a new zip file and add the four files (listed below) from the _Test folder created in step.
   • the 3 .appxysym files
   • the .appxbundle file
4. Rename the zip by changing the extension to .appxupload from .zip.
5. Uploaded this separately created appxupload file to the store.

This issue is reported to have been fixed in Update 5 for Visual Studio 2017 (https://www.visualstudio.com/en-us/news/releasenotes/vs2017-relnotes)