WCR: ImageDescriptionGenerator yields UnauthorizedAccessException in unpackaged scenarios

[riverar]

Describe the bug

After upgrading from exp1 to exp2, WCR ImageDescriptionGenerator now throws an unauthorized access exception. It's not clear why yet and is not documented as a known issue.

Further, it throws an exception with a duplicitous, non-standard, and unhelpful "Denied access".

Steps to reproduce the bug

1. Clone https://github.com/riverar/repro-64b8ca34
2. Deploy unpackaged and execute app on arm64 machine
3. Observe exception after clicking the Test button:

Exception thrown: 'System.UnauthorizedAccessException' in System.Private.CoreLib.dll
An exception of type 'System.UnauthorizedAccessException' occurred in System.Private.CoreLib.dll but was not handled in user code
Access is denied.

Denied access

Expected behavior

No exception or documentation regarding what hoops to jump through to get access.

Screenshots

No response

NuGet package version

Windows App SDK 1.8 Experimental 2: 1.8.250515001-experimental2

Packaging type

Unpackaged

Windows version

Insider Build (xxxxx)

IDE

No response

Additional context

No response

[mominshaikhdevs]

AI APIs now require MSIX (default | sparse). Unpackaged Apps are unsupported.

Ref:

https://github.com/microsoft/WindowsAppSDK-Samples/tree/main/Samples/WindowsAIFoundry/cs-winui#special-considerations-for-unpackaged-and-self-contained-modes-with-windows-ai-apis.

[riverar]

Would be great if the WCR team could confirm this is a permanent change.

[dabhattimsft]

Hi, I work on WCR team and can confirm this is the intended change.

[riverar]

Great, thanks @dabhattimsft!

[riverar]

Will point out, this seems to violate a Windows App SDK core principle of not requiring MSIX.