Windows Fundamentals for Legacy PCs (WINFLP), codenamed Edgar, is a thin client operating system released by Microsoft on July 8, 2006. It is a version of Windows XP that is made for older and less powerful hardware. Windows Fundamentals is not marked as a full-fledged general purpose operating system, though it is functionally able to perform most of the tasks generally associated with one. It includes only certain functionality for local workloads, such as security, management, the NET framework, and document viewing related tasks. It is designed to work as a client-server solution with RDP clients or other third party clients.


Windows Fundamentals for Legacy PCs was announced on May 12, 2005 with the code name "Eiger". The name Windows Fundamentals for Legacy PCs" appeared in a press release in September 2005.

The RTM version of Windows Fundamentals for Legacy PCs was released on July 8, 2006. The release was announced to the press on July 12, 2006.

Technical specifications

Microsoft positions WinFLP as an operating system that provides basic computing services on older hardware, while still providing management features of more recent Windows releases, such as Windows Firewall, Automatic Updates, and other services. However, it is not considered a general-purpose OS by Microsoft.

Windows Fundamentals for Legacy PCs is a Windows XP Embedded derivative and, as such, is optimized for legacy PCs. It requires significantly fewer system resources than the fully featured Windows XP. It also features basic networking, extended peripheral support, DirectX, and the ability to launch the remote desktop clients from compact discs. In addition to local applications, it offers support for those hosted on a remote server using Remote Desktop.

The installer for WinFLP uses a modern GUI based install process, similar to the one featured in Windows Vista.


In addition to giving better performance on older machines, the reduced number of files increases boot speed, and the reduced number of services also improves security and responsiveness.

Hardware requirements

  • CPU: Pentium 233 MHz (300 MHz recommended)
  • Memory: 64 MB (128 MB recommended)
  • Graphics hardware: 800 x 600 computer monitor
  • Hard disk space: 610 MB (1 GB recommended)
  • Network hardware: Optional

Despite being optimized for older computers, the hardware requirements are similar to Windows XP.


Windows Fundamentals for Legacy PCs has a smaller feature set than Windows XP. For example, Windows Fundamentals for Legacy PCs does not include things such as MS Paint, Outlook Express, and does not include Windows games such as Solitaire or Free Cell. Another noticeable limitation is that WinFLP does not include Compatibility mode.

Internet Explorer 8 (and 7) can be installed, but a hotfix is required for auto-complete to work in these newer versions of the browser.


WinFLP is exclusively available to Microsoft Software Assurance customers, and it is designed to be an inexpensive upgrade option for corporations that have a number of Windows 9x computers, but lack the hardware necessary to use the latest editions of Windows. It is not available through retail or OEM channels.

On October 7, 2008, Service Pack 3 for Windows Embedded for Point of Service and Windows Fundamentals for Legacy PCs was made available.

On April 18, 2013, Service Pack 3 for Windows Fundamentals for Legacy PCs (version 3) was made available.

The Microsoft marketing pages for Windows Fundamentals for Legacy PCs now redirect to those of Windows Thin PC, suggesting that Windows Fundamentals is no longer available for any customers.

Microsoft stated that WinFLP has the same lifecycle policy as Windows XP, and as such, Support for WinFLP ended on April 8, 2014.

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