A professional Windows tool to apply .1337 patch files directly into .exe or .dll files. Features both an intuitive GUI and a powerful command-line interface for automation.
- Apply .1337 patches to Windows executables (.exe) and libraries (.dll)
- Binary byte-level patching with validation and safety checks
- Automatic PE checksum recalculation after patching
- Certificate removal from PE files for modified binaries
- Automatic Target Detection - Auto-selects known system targets (e.g.,
nvEncodeAPI.dll) when matching patch is loaded
- Modern GUI with drag-and-drop support
- Settings persistence - remembers your last used files and preferences
- Case-preserving file dialogs - properly handles filename case sensitivity
- Visual feedback with detailed tooltips and status messages
- Full command-line interface for unattended/scripted patching
- Scheduled patching - schedule patches to run on next system boot (useful for locked files)
- Exit codes for integration with batch scripts and CI/CD pipelines
- Automatic backups - timestamped .BAK files before patching
- File ownership management - uses
takeownandicaclsfor protected files - Byte validation - verifies expected bytes before patching
- File offset adjustment - optional 0xC00 offset fix for specific use cases
- Windows 7 or later
- .NET Framework 4.5 or higher
- Administrator privileges (for taking ownership of protected files)
Download the latest release from the Releases page.
# Clone the repository
git clone https://github.com/ramhaidar/Win_1337_Apply_Patch.git
# Open the solution in Visual Studio
cd Win_1337_Apply_Patch
start Win_1337_Patch.sln
# Build the solution (Ctrl+Shift+B)
# Or build using dotnet CLI
dotnet build Win_1337_Patch.sln --configuration Release- Launch
Win_1337_Apply_Patch.exe - Select a
.1337patch file (or drag and drop it onto the window) - Select the target
.exeor.dllfile to patch (often auto-detected) - Configure options:
- Fix File Offset: Apply 0xC00 offset adjustment
- Create Backup: Save a timestamped backup before patching
- Change Ownership: Take ownership of protected system files
- Click Patch to apply
Win_1337_Apply_Patch.exe -patch <1337-file> <target-file> [options]| Option | Description |
|---|---|
-fileoffset, --fileoffset, -offset, --offset |
Apply 0xC00 file offset adjustment |
-backup, --backup, -b |
Create timestamped backup before patching |
-takeownership, --takeownership, -take-ownership |
Take ownership of protected files (requires admin) |
-schedule, --schedule, -runonce, -run-on-reboot |
Schedule patch to run on next boot |
-help, --help, /?, -h |
Show help text |
Basic patching:
Win_1337_Apply_Patch.exe -patch patch.1337 target.exePatch with backup and offset fix:
Win_1337_Apply_Patch.exe -patch patch.1337 target.exe -backup -fileoffsetPatch protected system file:
Win_1337_Apply_Patch.exe -patch patch.1337 C:\Windows\System32\target.dll -takeownership -backupSchedule patch for next boot:
Win_1337_Apply_Patch.exe -patch patch.1337 target.exe -schedule -backup| Code | Meaning |
|---|---|
| 0 | Success |
| 1 | Error (check console output for details) |
The .1337 patch file format is a simple text-based format:
>target.exe
<offset>:<expected_byte>-><replacement_byte>
Example:
>notepad.exe
1A3F:90->EB
1A40:00->90
- Line 1:
>followed by the expected target filename - Subsequent lines:
offset:expected->replacementin hexadecimal
Win_1337_Apply_Patch/
├── Win_1337_Patch/ # Main application
│ ├── PatchEngine.cs # Core patching logic
│ ├── ScheduledPatchManager.cs # Boot-time scheduling
│ ├── PatchTargetResolver.cs # Auto-target detection
│ ├── 1337.cs # GUI form
│ └── Program.cs # Entry point & CLI
├── Win_1337_Patch.Tests/ # Unit tests
│ ├── PatchEngineTests.cs
│ ├── ConsolePatchParserTests.cs
│ └── PatchTargetResolverTests.cs
└── Win_1337_Patch.sln # Solution file
The core patching engine (PatchEngine.cs) provides:
- Validation of patch files and target binaries
- Byte-level patching with safety checks
- Backup creation
- PE checksum normalization
- File ownership management
Automatically resolves target file paths for well-known patches (e.g., detecting System32\nvEncodeAPI.dll when nvencodeapi.1337 is loaded).
Handles scheduling patches to run on next boot via Windows RunOnce registry entries.
Parses command-line arguments with support for various option formats (implemented in Program.cs).
The project includes comprehensive unit tests:
# Run tests in Visual Studio
Test > Run All Tests
# Or use vstest.console
vtest.console.exe Win_1337_Patch.Tests.dll
# Or use dotnet CLI
dotnet test Win_1337_Patch.Tests/Win_1337_Patch.Tests.csproj- Patch application with backups
- Invalid header detection
- Target filename validation
- Byte mismatch detection
- CLI argument parsing
- Auto-target resolution
Contributions are welcome! Please:
- Fork the repository
- Create a feature branch (
git checkout -b feature/amazing-feature) - Commit your changes (
git commit -m 'Add amazing feature') - Push to the branch (
git push origin feature/amazing-feature) - Open a Pull Request
- Follow existing code style
- Add unit tests for new features
- Update documentation for API changes
- Ensure all tests pass before submitting
- Added: Automatic patch target resolution via
PatchTargetResolver, letting GUI and CLI flows auto-selectnvencodeapi.1337/nvencodeapi64.1337published underSystem32/SysWOW64without manual path hunting. - Added:
-patch/--patchCLI switch plus supporting console parser work so automated scripts can trigger patching without the GUI and share the same PatchEngine logic. - Added: Reboot scheduling through
ScheduledPatchManager, enabling patches to be staged for the next boot to handle locked DLLs and remote-admin scenarios. - Added: Dedicated
Select EXEbutton withTryAutoFillExecutable/SetExecutableTargethelpers so the GUI mirrors auto-detected targets while still allowing manual overrides. - Improved: Startup settings no longer retain
urlexeorurl1337, and executable/patch fields reset on load to guarantee every session starts from a predictable state. - Added: GPLv3 license file plus refreshed project metadata and configuration to make the fork’s legal posture explicit.
- Documented: Comprehensive README rewrite that now fully covers the GUI, CLI, architecture, automation story, and contributor/workflow guidance introduced in this release.
- Refined: PatchEngine now exposes consistent non-nullable
Succeededhelpers, centralizes CLI/GUI patch logic, and removes nullable noise so diagnostics and safety checks behave uniformly. - Added: MSTest project covering PatchEngine and ConsolePatchParser scenarios (addressing backups, validation failures, byte mismatches, and scheduling) to keep 100% coverage as the core logic evolves.
- Added: Command-line interface for automation
- Added: Scheduled patching for next boot
- Added: Unit test project with comprehensive coverage
- Added: File ownership management for protected files
- Added: Automatic backup creation with timestamps
- Refactored: Core patching logic moved to
PatchEngineclass - Fixed: Case sensitivity issues in file dialogs
- Improved: Error handling and user feedback
- Added: File offset fix option (0xC00 adjustment)
- Added: Settings persistence
- Improved: UI with drag-and-drop support
- Added: PE checksum recalculation
- Added: Certificate removal
- Initial: GUI implementation
This project is open source under the GPLv3 License. See the LICENSE file for details.
- Maintainer: @ramhaidar
- Fork Repository: https://github.com/ramhaidar/Win_1337_Apply_Patch
- Original Author: DeltaFoX (DeFconX)
- Copyright: © 2026
- OriginalRepository: https://github.com/Deltafox79/Win_1337_Apply_Patch
For issues, feature requests, or questions:
- Open an issue on GitHub
- Check existing issues before creating new ones
Warning: Patching executable files can cause them to malfunction. Always create backups before patching and use at your own risk.