Win10/Win11 Detection: How WSA Installer Selects the Right Build

The Problem

WSA was built for Windows 11. On Windows 10, it crashes because WsaClient.exe calls APIs that don't exist on the older OS. Different builds are needed for each Windows version.

How Detection Works

WSA Installer uses Windows build numbers to determine your OS version:

import sys

version = sys.getwindowsversion()
if version.major == 10:
    if version.build >= 22000:
        # Windows 11 (build 22000+)
        is_win11 = True
    else:
        # Windows 10 (build 19041-21999)
        is_win11 = False
else:
    # Unknown Windows version
    is_win11 = False

Windows 11 Path

Standard WSA Builds

Windows 11 users get the standard WSA builds directly from Microsoft/WSABuilds:

• Build: 2407.40000.4.0 (latest)
• No additional patches required
• Full GPU acceleration support
• All features work out of the box

GitHub Source

Source: WSA-Installer/wsa-installer
Build: 2407.40000.4.0
Architecture: x64
GApps: MindTheGapps 13.0

Windows 10 Path

WSAPatch Builds

Windows 10 users get WSAPatch-compatible builds with binary patches:

• Build: 2407.40000.4.0 (patched)
• WsaClient.exe binary patched for Win10
• API calls replaced with compatible equivalents
• Some graphics limitations (ANGLE fallback)

What WSAPatch Does

WSAPatch modifies WsaClient.exe to replace unsupported API calls:

Original (Win11):
  CreateSymbolicLinkW → CreateSymbolicLinkW
  GetProductInfo → GetProductInfo

Patched (Win10):
  CreateSymbolicLinkW → CreateSymbolicLinkW (compat)
  GetProductInfo → GetVersionExW (fallback)

Detection in Practice

Here's how the detection flows through the installer:

• 1. User runs installer
• 2. Phase 1: System Validation detects Windows version
• 3. If Win11 → Use standard builds
• 4. If Win10 → Use WSAPatch builds
• 5. Download appropriate build
• 6. If Win10 → Apply WSAPatch during installation
• 7. Complete installation

Version Matrix

• Windows 11 22H2+ (build 22000+) → WSA 2407.40000.4.0 → No patches
• Windows 11 21H2 (build 22000) → WSA 2407.40000.4.0 → No patches
• Windows 10 21H2 (build 19044) → WSA 2407.40000.4.0 → WSAPatch
• Windows 10 21H1 (build 19043) → WSA 2407.40000.4.0 → WSAPatch
• Windows 10 2004 (build 19041) → WSA 2407.40000.4.0 → WSAPatch
• Windows 10 < 19041 → Not supported

Troubleshooting

Wrong Build Selected

• Check Windows version: winver
• Verify build number in System Properties
• Report issue on GitHub

WSAPatch Failed

• Check if WsaClient.exe exists
• Verify file permissions
• Try running installer as administrator
• Check wsa_activity.log for errors

Future Plans

Future versions will add:

• ARM64 Windows support (Snapdragon PCs)
• Automatic WSAPatch updates
• Build selection override (advanced users)
• Multi-version support (install multiple WSA versions)