WindowsAppSDK 1.7.x breaks React Native Windows build (LNK1104 – win10- path bug)

Problem Description

React Native Windows build fails due to an invalid library path generated by
Microsoft.WindowsAppSDK 1.7.x.

The build system resolves this path incorrectly:
lib\win10-\Microsoft.WindowsAppRuntime.Bootstrap.lib

Architecture value is missing (win10- instead of win10-x64),
which causes a linker failure.

Downgrading WindowsAppSDK to 1.6.x fixes the issue.

Steps To Reproduce

Steps To Reproduce *

Create new project
npx react-native init RNWinTest

Add Windows support
npx react-native-windows init-windows

Build
npx react-native run-windows --arch x64

Build fails with LNK1104 error.

Expected Results

Build should complete successfully and launch the app.

Expected correct path:
lib\win10-x64\Microsoft.WindowsAppRuntime.Bootstrap.lib

CLI version

@react-native-community/cli: 20.0.0

Environment

OS: Windows 11 (x64)

Node: v22.x (via NVM)

Yarn: latest

React Native: 0.81.5

React Native Windows: 0.81.2

Windows App SDK (NuGet): 1.7.250401001

Windows App Runtime (system): 1.8.4 (x64)

Community Modules

react-native-gesture-handler

react-native-reanimated

react-navigation

axios

react-native-screens

Target React Native Architecture

New Architecture (WinAppSDK) Only

Target Platform Version

= 10.0.26100

Visual Studio Version

Visual Studio 2022

Build Configuration

Debug

Snack, code example, screenshot, or link to a repository

Minimal repro:
npx react-native init RNWinTest npx react-native-windows init-windows npx react-native run-windows --arch x64

Error:
LINK : fatal error LNK1104: lib\win10-\Microsoft.WindowsAppRuntime.Bootstrap.lib