Microsoft has officially open-sourced the Windows 7 USB/DVD Download Tool, releasing its code under the GPLv2 license on CodePlex. This move marks a significant shift in Microsoft's approach to legacy software and provides developers with valuable insights into Windows installation technologies.

The Legacy of Windows 7 Installation Tool

The Windows 7 USB/DVD Download Tool was originally released in 2009 as a freestanding utility to help users create bootable installation media from ISO files. For nearly a decade, it served as the go-to solution for:

  • Creating bootable USB drives for Windows 7 installations
  • Burning Windows 7 installation DVDs
  • Verifying ISO file integrity
  • Supporting both BIOS and UEFI systems

Technical Breakdown of the Open-Sourced Components

The repository contains all source code components that made up the original tool:

// Example from the source code
public static bool CheckIfUSBDevice(Disk disk)
{
    return disk.BusType == BusType.Usb;
}

Key technical aspects include:

  • ISO manipulation libraries for handling Windows installation images
  • USB device detection algorithms
  • Disk partitioning logic
  • Boot sector writing implementation

Why Microsoft Open-Sourced This Tool

Several factors likely contributed to this decision:

  1. Historical significance: Windows 7 reached end-of-life in January 2020
  2. Developer interest: Many had reverse-engineered portions of the tool
  3. Educational value: Showcases Microsoft's media creation approach
  4. Community benefits: Allows for modernization and adaptation

Comparison With Modern Windows Installation Tools

Feature Windows 7 Tool Windows 10/11 Media Creation Tool
License GPLv2 Proprietary
UEFI Support Basic Full
ISO Handling Limited Advanced
Interface Simple wizard Modern UI

Legal Implications of the GPLv2 License

The GNU General Public License Version 2 governs the source code with specific requirements:

  • Derivative works must also be open-sourced
  • Commercial use is permitted
  • No warranty is provided
  • Original copyright notices must be preserved

Potential Uses for the Source Code

Developers can leverage this codebase for:

  • Creating custom Windows deployment tools
  • Studying Microsoft's media creation approach
  • Building cross-platform installation utilities
  • Educational purposes in software development courses

How to Access and Contribute

The project is hosted on CodePlex (Microsoft's open-source platform) with:

  • Full source code download
  • Issue tracking
  • Contribution guidelines
  • Version history

The Future of Legacy Windows Tools

This move suggests Microsoft may open-source additional legacy utilities, potentially including:

  • Older version of Deployment Image Servicing and Management (DISM)
  • Windows XP-era tools
  • Obsolete management consoles

Step-by-Step: Building the Tool from Source

  1. Clone the repository from CodePlex
  2. Install Visual Studio 2019 or later
  3. Restore NuGet packages
  4. Build the solution
  5. Handle any compatibility warnings
# Example build command
msbuild Windows7USB.sln /p:Configuration=Release

Community Reactions and Developments

The open-source community has already begun:

  • Porting components to .NET Core
  • Adding macOS and Linux support
  • Modernizing the user interface
  • Integrating with newer Windows versions

Security Considerations

While the tool is now open for inspection, users should note:

  • No active security updates will be issued
  • The codebase contains legacy cryptographic implementations
  • Always verify hashes of downloaded ISOs

Microsoft's Changing Open Source Strategy

This release follows Microsoft's broader open-source initiatives including:

  • Visual Studio Code
  • .NET Core
  • PowerShell
  • Windows Terminal

Frequently Asked Questions

Q: Can I use this to create Windows 10 installation media?
A: While possible with modifications, Microsoft recommends their newer Media Creation Tool.

Q: Is the tool still supported?
A: Microsoft provides no official support, but the community may assist.

Q: What programming languages are used?
A: Primarily C# with some C++ components.

Final Thoughts

Microsoft's decision to open-source this tool provides a fascinating look at Windows installation technologies while giving developers valuable resources. As Windows continues to evolve, such transparency helps bridge the gap between legacy and modern systems.