A command-line utility for Windows XP and later that allows you to run applications with spoofed Windows version information, making them think they're running on Windows Vista, 7, 8, 10, or 11.

• Extended Version Support: Spoof Windows Vista, 7, 8, 10, and 11
• Windows XP Compatibility: Runs on Windows XP SP3 and later systems (x86)
• Command-line Interface: Easy to use with simple parameters
• Shortcut Compatible: Create shortcuts for frequently used applications
• Environment Variable Injection: Uses Windows compatibility layers and environment variables
• Lightweight: Built on .NET Framework 4.0 for maximum compatibility

compat.exe /e <executable_path> /v <windows_version>

• /e <path> - Path to the executable to run
• /v <version> - Windows version to spoof (vista, 7, 8, 10, 11)
• /? - Show help message

# Run Chrome thinking it's on Windows 11
compat.exe /e "C:\Program Files\Google\Chrome\Application\chrome.exe" /v 11

# Run an application thinking it's on Windows 7
compat.exe /e "C:\Program Files\OldApp\oldapp.exe" /v 7

# Run Notepad thinking it's on Windows Vista
compat.exe /e "C:\Windows\System32\notepad.exe" /v vista

# Run custom application with Windows 8 compatibility
compat.exe /e "C:\Program Files\Test\test.exe" /v 8

The tool works by:

1. Environment Variables: Sets compatibility environment variables like __COMPAT_LAYER and __MS_COMPAT_LEVEL
2. Process Environment: Injects version-specific environment variables into the target process
3. Windows Compatibility Layer: Uses Windows built-in compatibility systems
4. Build Number Spoofing: Sets appropriate build numbers and version information for the target Windows version
5. Architecture Compatibility: Sets x86 architecture for Windows XP compatibility

This project requires .NET Framework 4.0 or later.

# Debug build
dotnet build

# Release build
dotnet build -c Release

# Build for Windows x86 (for Windows XP compatibility)
dotnet publish -c Release -r win-x86 -f net40

• Windows XP SP3 or later
• .NET Framework 4.0 or later
• x86 or x64 architecture

• Applications that check Windows version information through environment variables
• Applications that respect Windows compatibility layers

The tool uses several methods to spoof Windows version information:

• __COMPAT_LAYER environment variable for compatibility layer activation
• __MS_COMPAT_LEVEL for specific build number spoofing
• WINDOWS_VERSION and WINDOWS_BUILD for additional version checks
• WINDOWS_MAJOR_VERSION and WINDOWS_MINOR_VERSION for detailed version info
• PROCESSOR_ARCHITECTURE for architecture compatibility (set to x86)

• VISTARTM: Windows Vista compatibility
• WIN7RTM: Windows 7 compatibility
• WIN8RTM: Windows 8 compatibility
• WIN10RTM: Windows 10 compatibility
• WIN10RTM WIN11: Windows 11 compatibility

Run modern applications on older Windows systems:

# Run a Windows 10-only app on Windows 8.1
compat.exe /e "C:\Program Files\ModernApp\app.exe" /v 10

Test applications with different Windows version targets:

# Test how your app behaves on Windows 7
compat.exe /e "C:\MyApp\myapp.exe" /v 7

Force applications to use older compatibility modes:

# Run problematic app with Vista compatibility
compat.exe /e "C:\Program Files\ProblematicApp\app.exe" /v vista

1. Right-click on desktop → "New" → "Shortcut"
2. Enter: "C:\path\to\compat.exe" /e "C:\Program Files\YourApp\app.exe" /v 11
3. Name your shortcut (e.g., "MyApp (Win11 Mode)")

Use the included PowerShell script to automatically create shortcuts.

• Only supports Windows Vista, 7, 8, 10, and 11 spoofing
• Requires target applications to respect environment variables
• Some applications may use alternative methods to detect Windows version
• Administrative privileges may be required for some applications
• x86 build recommended for maximum compatibility with Windows XP

This tool is specifically designed to work on Windows XP SP3 and later:

• Built with .NET Framework 4.0 (last version to support Windows XP)
• x86 architecture for maximum compatibility
• Uses only Windows APIs available on Windows XP
• Minimal dependencies for easy deployment

This project is provided as-is for educational and compatibility purposes.