In context: Windows 7 as a proper computing platform has long been dead, but leakers are still playing with the corpse of one of Microsoft most successful software products. A new preview build of the operating system is now available online, providing an interesting addition for Windows historians and Win32 software enthusiasts.

Microsoft ended the official extended support for Windows 7 in January 2020, but Windows 7 is still making news. An old beta build of the OS recently leaked online, offering a glimpse of how development was going back in July 2008.

The final RTM version of Windows 7 would be released about a year later, and this old beta build includes some of the changes customers experienced with the OS on their 2009 PC.

BetaWiki has a comprehensive article about the changes introduced in Windows 7 build 6758, which is a "Milestone 3" build of Windows 7. The build was compiled on July 24, 2008, with an expiration date set to April 1, 2009. Build 6758 was recently uploaded to the Internet Archive, where client (x86) and server (x64) ISO disk images are now available for download.

The build includes an updated Paint application which is similar to the version included in Windows 7 RTM, plus a series of major changes to the underlying features and design of the OS. Improvements to previously available (and publicly known) builds affect the Windows Setup process, Control Panel applets, the Shell, the Start Menu, and more.

According to BetaWiki, the Windows Explorer user interface was significantly updated when compared to previous OS builds. Meanwhile, the Start Menu was modified to include links to users' documents, picture and video libraries by default. The Desktop Window Manager, which was created to enable the distinct "Aero experience" of Windows Vista and still is an essential component in Windows 10 and 11, includes new animations for the Aero Snap feature.

Additional changes included in build 6758 affect the Desktop Gadget Gallery, which no longer runs by default, a leaner User Account Control (UAC) experience, Notification Tray design, system flyouts. Improved applications included Internet Explorer, which has new interface components, media-related programs (Windows Media Center, Windows Media Player, Windows DVD Maker), and several system components. The humble Calculator had a slick new interface which unfortunately was toned down for the RTM.

Windows enthusiasts can try to install and run the Windows 7 build within a virtual machine like VMware Player, which offers excellent support for the historic OS. Microsoft is still providing security patches for the Windows Embedded POSReady 7 version of Windows 7, but the Extended Security Updates program will finally expire on October 8, 2024.