I want to build universal app for release on the store i.e. generating the *.appxupload (building the *.appx to deploy on my machine is fine; have to remove the default /p:AppxBundle=Always though and cannot build Win32: no matter what I do, it always builds ARM). But I cannot get it to work at all following Microsoft's instructions i.e. adding /p:UapAppxPackageBuildMode=CI.
The system simply stops with
Error MSB4126: The specified solution configuration "Release|x86" is invalid. Please specify a valid solution configuration using the Configuration and Platform properties (e.g. MSBuild.exe Solution.sln /p:Configuration=Debug /p:Platform="Any CPU") or leave those properties blank to use the default solution configuration.
My project has obviously an Release|x86 configuration. And it reports this while building ARM release. I tried changing x86 to Win32 but it then report
APPX0502: File 'C:\a\1\s\AppName\BundleArtifacts\Win32.txt' not found. [C:\a\1\s\AppName\AppName.vcxproj]
EDIT: Apparently, I have to manually set the Project to Win32 for it to build x86 release. Previously, it was left blank (and the automatic build configuration generator also leaves it blank).
