Microsoft.AI.Foundry.Local.WinML 1.2.3 ships duplicate Microsoft.Windows.AI.MachineLearning.dll causing APPX1101 in packaged WinUI apps

[nmetulev]

Summary

Microsoft.AI.Foundry.Local.WinML 1.2.3 (via its transitive Microsoft.AI.Foundry.Local.Core.WinML 1.2.3) ships a redundant private copy of Microsoft.Windows.AI.MachineLearning.dll in its own runtimes/<rid>/native folder, while also taking a package dependency on Microsoft.Windows.AI.MachineLearning 2.1.70 — the canonical package that already owns that DLL.

In an MSIX-packaged WinUI 3 app, both copies resolve to the same payload destination path and the build fails with APPX1101: Payload contains two or more files with the same destination path.

Error

error APPX1101: Payload contains two or more files with the same destination path
'Microsoft.Windows.AI.MachineLearning.dll'. Source files:
  ...\microsoft.windows.ai.machinelearning\2.1.70\runtimes\win-arm64\native\Microsoft.Windows.AI.MachineLearning.dll
  ...\microsoft.ai.foundry.local.core.winml\1.2.3\runtimes\win-arm64\native\Microsoft.Windows.AI.MachineLearning.dll

(Same failure occurs for win-x64.)

Minimal repro (stock template + one package)

dotnet new winui -n WinMLDupeRepro
cd WinMLDupeRepro
dotnet add package Microsoft.AI.Foundry.Local.WinML --version 1.2.3
dotnet build -p:Platform=ARM64 -c Debug

The blank WinUI template references Microsoft.WindowsAppSDK 2.2.0, which transitively brings the canonical Microsoft.Windows.AI.MachineLearning 2.1.70. Adding the Foundry WinML package introduces the duplicate, and a plain packaged build fails. No extra configuration is needed.

Dependency graph (dotnet nuget why ... microsoft.windows.ai.machinelearning)

'microsoft.windows.ai.machinelearning':
  ├── Microsoft.AI.Foundry.Local.WinML (v1.2.3)
  │   └── Microsoft.AI.Foundry.Local.Core.WinML (v1.2.3)
  │       └── Microsoft.Windows.AI.MachineLearning (v2.1.70)
  └── Microsoft.WindowsAppSDK (v2.2.0)
      └── Microsoft.WindowsAppSDK.ML (v2.1.70)
          └── Microsoft.Windows.AI.MachineLearning (v2.1.70)

NuGet correctly unifies the canonical Microsoft.Windows.AI.MachineLearning package to a single 2.1.70. The collision is not a version conflict — it is the extra, redundant Microsoft.Windows.AI.MachineLearning.dll that microsoft.ai.foundry.local.core.winml 1.2.3 bundles itself:

microsoft.ai.foundry.local.core.winml\1.2.3\runtimes\win-arm64\native\Microsoft.Windows.AI.MachineLearning.dll
microsoft.ai.foundry.local.core.winml\1.2.3\runtimes\win-x64\native\Microsoft.Windows.AI.MachineLearning.dll

Expected

Microsoft.AI.Foundry.Local.Core.WinML should not re-ship Microsoft.Windows.AI.MachineLearning.dll (or any other binary already owned by the Microsoft.Windows.AI.MachineLearning / Microsoft.WindowsAppSDK.ML package it depends on). It should consume that DLL from the canonical package so there is exactly one copy in the MSIX payload.

Actual

Two copies of Microsoft.Windows.AI.MachineLearning.dll are placed at the same payload path → APPX1101 → packaged build fails.

Workaround

Strip the Foundry copy from the payload via an MSBuild target:

<Target Name="DedupeFoundryWinML" AfterTargets="ResolveAssemblyReferences"
        BeforeTargets="_GenerateAppxPackage;GenerateAppxPackage;_CopyFilesMarkedCopyLocal">
  <ItemGroup>
    <ReferenceCopyLocalPaths Remove="@(ReferenceCopyLocalPaths)"
      Condition="'%(FileName)%(Extension)' == 'Microsoft.Windows.AI.MachineLearning.dll' and $([System.String]::Copy('%(FullPath)').Contains('microsoft.ai.foundry.local.core.winml'))" />
    <None Remove="@(None)"
      Condition="'%(FileName)%(Extension)' == 'Microsoft.Windows.AI.MachineLearning.dll' and $([System.String]::Copy('%(FullPath)').Contains('microsoft.ai.foundry.local.core.winml'))" />
    <Content Remove="@(Content)"
      Condition="'%(FileName)%(Extension)' == 'Microsoft.Windows.AI.MachineLearning.dll' and $([System.String]::Copy('%(FullPath)').Contains('microsoft.ai.foundry.local.core.winml'))" />
  </ItemGroup>
</Target>

(The same package also redundantly ships onnxruntime.dll, which needs an equivalent dedupe — likely the same root cause.)

Environment

• Microsoft.AI.Foundry.Local.WinML 1.2.3 / Microsoft.AI.Foundry.Local.Core.WinML 1.2.3
• Microsoft.WindowsAppSDK 2.2.0 / Microsoft.WindowsAppSDK.ML 2.1.70 / Microsoft.Windows.AI.MachineLearning 2.1.70
• Microsoft.Windows.SDK.BuildTools.MSIX 1.7.251221100
• .NET 10, net10.0-windows10.0.26100.0, WinUI 3 single-project MSIX
• RIDs affected: win-arm64, win-x64