CBFS Shell

The easiest way to extend and customize Windows Explorer with virtual folders, custom menus, toolbars, details columns and more!

Download beta
The latest beta of CBFS Shell has a new & simplified API.

Three new components allow your application to extend Windows Explorer with ease [learn more].
CBFS Shell

Windows Explorer Customization

Enhance your users' Windows Explorer experience with CBFS Shell. Enable them to seamlessly interact with files and folders, tailor context menus to their needs, incorporate informative columns, and more. Unlike in-process code that risks crashing the Explorer process, CBFS Shell operates independently, communicating with your application through a robust RPC mechanism. Windows Explorer and other applications remain stable and unaffected by unexpected or unhandled conditions within your shell application.

Supported operations include:

Greater Explorer Stability

Only our unique proxy runs in the Explorer process, which calls your code via local RPC. Your code runs out of process, keeping Explorer stable and responsive. This configuration is what enables you to use managed .NET code to create Shell Namespace Extensions.

Virtual Folders

CBFS Shell can be used to easily create and manage Virtual Folders (display custom data as files) with the help of a Windows Shell Namespace Extension. Data can be read from essentially any source or created on-demand. When a user navigates into a Virtual Folder, the data is presented as a tree of folders and files, just like any other folder.

Additional Views and Visual Information

CBFS Shell's standard namespace also includes other UI elements you can customize, such as:

  • Details View, List View, and Icon View
  • Thumbnails and Tooltips
  • Property Pages
  • Toolbars and Ribbons

Complete Navigation and Menu Options

CBFS Shell allows your application to handle many standard End-User Actions on files and folders, such as:

  • Context Menus (with standard or specific items)
  • Copy, Paste, Cut, Delete, Link, Drag and Drop
  • Go To, Backward, Forward, Level Up, Level Down
  • Grouping and Filtering
  • Searching

Custom Columns

CBFS Shell allows you to customize which columns are visible within the detail view of Windows Explorer. Choose from many pre-defined options or create your own columns. Both text and icons can be displayed in a Custom Column. CBFS Shell allows you to present items within a folder in a way that best fits your specific use case.

Supported Platforms


High Performance .NET Components

A managed .NET component layer packaged with a high-performance native shell extension.

  • Support for .NET 8, .NET 7, .NET 6, .NET 5, and .NET Core 3.1.
  • Extensive sample applications written in C#.
  • Comprehensive integrated product documentation.
  • Seamless integration with Visual Studio.
  • Support for .NET Framework 4.7 - 4.8.2
  • .NET Standard 2.0 and 2.1 support.


The following components are included in CBFS Shell.

Included Samples

The following samples are installed with the product. Please download the trial to get started.

Device Manager
A virtual folder that represents the Windows Device Manager, where devices and their categories are represented as virtual items and folders.
Platforms: .NET Core
Shows how to use the ShellFolder component to import files into a virtual folder and export virtual file contents to third-party applications.
Platforms: .NET Core
Shows how to use the ShellFolder component to create a simple virtual folder that contains a fixed set of virtual items and folders.
Platforms: .NET Core
Registry Folder
A virtual folder that represents the Windows Registry, where registry keys and directories are represented as virtual items and folders.
Platforms: .NET Core
Shell Menu
Shows how to use the ShellMenu component to add a custom context menu item to any Windows Shell items selected in the Windows File Explorer.
Platforms: .NET Core
Shell Notify
Shows how to use the simple ShellNotify component to monitor changes in a specified path.
Platforms: .NET Core