7-Zip Explorer Extension

A Windows 11 context menu shell extension that integrates 7-Zip into the modern right-click menu — no more digging through "Show more options."

Features

• Modern context menu — appears in the top-level Windows 11 right-click menu
• Dynamic labels — shows actual filenames (e.g., Extract to "project\", Add to "photos.7z")
• Smart visibility — extract/test commands only appear for archive files
• Full 7-Zip integration — delegates to 7zG.exe, 7zFM.exe, and 7z.exe

Context Menu Items

Command	Description
Open archive	Opens in 7-Zip File Manager
Extract files...	Extract with options dialog
Extract Here	Extract to current directory
Extract to "name\"	Extract to a named subfolder
Test archive	Verify archive integrity
Add to archive...	Compress with options dialog
Compress and email...	Compress and attach to email
Add to "name.7z"	Quick compress to .7z
Add to "name.zip"	Quick compress to .zip
Compress to "name.7z" and email	Compress to .7z and email
Compress to "name.zip" and email	Compress to .zip and email

Prerequisites

• Windows 11 (build 19041+)
• 7-Zip installed (download)
• .NET 10 SDK
• Visual Studio 2022/2026 (or Build Tools) with the Desktop development with C++ workload — Native AOT links the native image with the MSVC toolchain
• Windows 10/11 SDK — provides makeappx.exe / signtool.exe used by install.ps1

Building

Using the build script (recommended)

.\scripts\build.ps1

This publishes the Native AOT COM DLL to build\Release\7ZipMenu.dll. It works from any shell — Native AOT locates the MSVC linker itself. The MSIX sparse package is assembled later by install.ps1.

Using dotnet directly

dotnet publish src\7ZipMenu\7ZipMenu.csproj /p:Configuration=Release /p:Platform=x64

Native AOT compiles the DLL to native code, so the Desktop development with C++ workload (MSVC toolchain) must be installed.

Using Visual Studio

Open 7ZipMenu.slnx in Visual Studio 2022/2026 and build. The solution contains three projects:

Project	Output	Purpose
7ZipMenu	7ZipMenu.dll	COM DLL shell extension (Native AOT)
7ZipMenuStub	7ZipMenuStub.exe	Stub required by the MSIX schema
Package	.msix	Windows Application Packaging Project

Installation

1. Create a development certificate (first time only)

Run as Administrator:

.\scripts\create-certificate.ps1

This creates a self-signed certificate and trusts it for sideloading.

2. Install the extension

Run as Administrator:

.\scripts\install.ps1

This will:

1. Package the sparse MSIX
2. Sign it with the dev certificate
3. Register it with Windows
4. Restart Explorer

3. Verify

Right-click any file in Explorer — you should see 7-Zip in the modern context menu.

Uninstallation

.\scripts\uninstall.ps1

How It Works

The extension is a COM DLL (7ZipMenu.dll) written in C# and compiled ahead-of-time with .NET Native AOT. It implements the IExplorerCommand interface via source-generated COM interop ([GeneratedComInterface] / [GeneratedComClass]), so the target machine needs no .NET runtime installed. It registers via a sparse MSIX package to gain the app identity required by Windows 11's modern context menu.

Explorer (right-click)
  └─ Loads 7ZipMenu.dll (in-process COM)
       └─ IExplorerCommand::EnumSubCommands → returns all menu items
       └─ IExplorerCommand::GetTitle → dynamic labels from IShellItemArray
       └─ IExplorerCommand::GetState → hides extract items for non-archives
       └─ IExplorerCommand::Invoke → launches 7zG.exe / 7zFM.exe / 7z.exe

Architecture

Component	Purpose
ExplorerCommandBase	Base class with shared IExplorerCommand implementation
SevenZipRootCommand	Top-level "7-Zip" cascading menu (COM-registered CLSID)
SubCommands	12 leaf commands with dynamic titles and smart visibility
CommandEnumerator	IEnumExplorerCommand for Explorer to discover subcommands
SevenZipUtils	Finds 7-Zip installation via registry, detects archive file types
Sparse MSIX	Provides app identity for Windows 11 modern menu registration

7-Zip Detection

The extension searches for 7-Zip in this order:

1. Registry: HKLM\SOFTWARE\7-Zip\Path64 / Path
2. Registry: HKCU\SOFTWARE\7-Zip\Path64 / Path
3. C:\Program Files\7-Zip\
4. C:\Program Files (x86)\7-Zip\

Project Structure

├── 7ZipMenu.slnx               # Visual Studio solution (XML format)
├── src/
│   ├── 7ZipMenu/               # COM DLL shell extension (C# / Native AOT)
│   │   ├── 7ZipMenu.csproj
│   │   ├── DllExports.cs           # DllGetClassObject / DllCanUnloadNow exports
│   │   ├── ClassFactory.cs         # IClassFactory implementation
│   │   ├── ExplorerCommandBase.cs  # Base IExplorerCommand implementation
│   │   ├── SevenZipRootCommand.cs  # Top-level "7-Zip" cascading menu
│   │   ├── CommandEnumerator.cs    # IEnumExplorerCommand
│   │   ├── SevenZipUtils.cs         # 7-Zip path discovery + archive detection
│   │   ├── NativeMethods/           # COM interface & enum definitions
│   │   └── SubCommands/             # Leaf commands (extract / compress / etc.)
│   ├── 7ZipMenuStub/           # Stub executable required by the MSIX schema
│   └── Package/                # Windows Application Packaging Project (.wapproj)
├── manifest/
│   ├── AppxManifest.xml        # Sparse package manifest
│   └── dllmanifest.manifest    # Embedded activation manifest
├── scripts/
│   ├── build.ps1               # Build the Native AOT DLL via `dotnet publish`
│   ├── create-certificate.ps1  # Dev certificate setup
│   ├── install.ps1             # Package, sign, and register
│   └── uninstall.ps1           # Remove extension
├── sparse-package/             # MSIX staging directory
└── old/                        # Legacy C++/WRL implementation (archived)

License

MIT