The Role of MSIX in Modernizing Legacy Windows Applications

MSIX is a Windows app package format that provides a modern packaging experience to all Windows apps.

The MSIX package format preserves the functionality of existing app packages and/or install files in addition to enabling new, modern packaging and deployment features to Win32, WPF, and Windows Forms apps.

Combining the best features of MSI and AppX, MSIX offers a versatile solution for developers and IT administrators, supporting both Win32 and Universal Windows Platform (UWP) apps.

Modernizing Legacy Apps

Legacy Windows applications refer to software programs that were developed using older technologies and frameworks, often running on outdated operating systems, typically built using technologies such as Visual Basic, C++, or .NET Framework. These applications may have served their purpose well in the past, but as technology advances, they can become a liability for businesses.

Common characteristics of legacy Windows applications include a lack of compatibility with modern operating systems, dependency on outdated frameworks and libraries, outdated user interfaces, performance issues, security vulnerabilities and difficulty in integrating with other systems.

MSIX and MSIX App Attach

Microsoft’s App-V solution is the most commonly used application virtualization and delivery solution for enterprise organizations worldwide. However, after having no new features added for years now, App-V officially will become end of life in 2026. Its successor is ‘MSIX’ – The two are compared here.

MSIX simplifies app installation, updates, and uninstallation with a clean, reliable process that minimizes system impact. It supports seamless updates through the Microsoft Store or enterprise systems, ensuring users always have the latest versions.

The format enhances security with containerization, isolating apps to prevent conflicts and reduce vulnerabilities. MSIX also optimizes disk space by sharing components across apps and supports differential updates to reduce bandwidth usage.

For developers, MSIX offers a unified packaging format, reducing the need for multiple installers. It integrates with modern deployment tools like Intune and supports sideloading for enterprise flexibility. IT administrators benefit from simplified app management, as MSIX ensures consistent deployment across devices, from desktops to IoT. Its compatibility with legacy systems makes it ideal for organizations transitioning to modern workflows.

As Microsoft describes here the Azure Virtual Desktop related innovation to application management is a new feature called MSIX app attach, a packaging format that offers many features aimed to improve packaging experience for all Windows apps. MSIX app attach is a way to deliver MSIX applications to both physical and virtual machines, simplifying the deployment process by providing a single package that can be installed on any Windows 10 device.

MSIX app attach is different from regular MSIX because it’s made specifically for Azure Virtual Desktop. This creates separation between user data, the operating system, and applications by using MSIX containers. You can remove the need for repackaging when you deliver applications dynamically. You can reduce the time it takes for a user to sign in to Azure Virtual Desktop, and at the same time reduce infrastructure requirements and cost.

App Attach is a feature in Windows Virtual Desktop that allows applications to be dynamically attached to virtual machines. It eliminates the need for traditional image management and enables administrators to deliver applications on-demand.

Best Practices

In this webinar the hosts provide an overview of MSIX and app attach, two technologies that simplify application deployment and management in Windows environments.

The video provides an informative overview of MSIX and app attach. These technologies offer significant advantages in simplifying application deployment and management in Windows environments. By adopting MSIX and leveraging App Attach, organizations can enhance their application delivery processes, improve security, and reduce storage costs. The video highlights several benefits of using MSIX and App Attach:

• Streamlined application packaging and deployment.
• Improved security and reliability.
• Reduced storage costs.
• Flexibility in delivering applications to virtual machines.
• Compatibility with existing deployment tools.