With my colleague created Blank App, Package (WinUI3 in Desktop) having a goal to learn this new technology. After just a few minor changes (added ItemsControl and three buttons) my colleague has started to receive the abovementioned error message (note that I preserved the original error syntax “…its does not declare…”) when deploying from Visual Studio 2019 Enterprise on his development PC (Windows 10 20H2). Whereas it deploys fine onto my development PC (Windows 10 1909).
There is a large number of complains and potential solutions to this problem on the Internet; none of those has helped.
Running Get-AppPackageLog -ActivityID <ID> yields this:
794 Windows cannot install package <ID> because its does not declare support for an external location.
605 The last successful state reached was BundleProcessed. Failure occurred before reaching the next state Indexed. hr: 0x80070032
401 Deployment Add operation with target volume C: on Package <ID> from: (<name>NULL(Package)_1.0.2.0_x64.msixbundle) failed with error 0x80070032. See http://go.microsoft.com/fwlink/?LinkId=235160 for help diagnosing app deployment issues.
404 AppX Deployment operation failed for package <ID> with error 0x80073CF9. The specific error text for this failure is: Windows cannot install package <ID> because its does not declare support for an external location.
Thank you in advance for any help.
Eugene