Windows NT 4 went on sale 30 years ago today

OS PLatforms

The version that started to bring all Microsoft’s pieces together

Today marks the 30th anniversary of Microsoft Windows NT 4.0 becoming available on August 24, 1996.

Windows NT 4.0, codenamed “Tukwila,” went on retail sale exactly 30 years ago. This was the version that started to deliver on the promise of Microsoft’s long-running Windows NT project. NT 4 married the very solid NT operating system with a slightly modified version of the Windows Explorer desktop from Windows 95, which is why it was also internally known as the “Shell Update Release”. NT 4 had been released to manufacturing on July 31.

As it happens, Windows 95 itself was launched exactly one year earlier, on August 24, 1995. Codenamed “Chicago” and originally planned to be called “Windows 4”, Windows 95 went through a long, iterative development process during which the desktop shell changed dramatically.

Various unfinished versions leaked over the years, and the excellent ToastyTech has screenshot tours of Windows Chicago Build 58 and Build 73 in which you can see the UI taking shape. In early versions, programs didn’t minimize to the taskbar yet, and the prototype Start Button didn’t do much.

By 31 years ago, the Explorer desktop had come together enough to launch. Explorer had some missteps. For instance, Windows 95 had no web browser; that was a paid-for optional extra in the Windows 95 Plus! Pack, along with Space Cadet Pinball. Instead, Windows 95 had a desktop icon for the Microsoft Network (MSN), a dial-up social network that displayed forums and participant lists using desktop file-explorer style windows, in an effort to blur the lines between local and remote resources.

Some of the features of the Explorer desktop were to avoid stepping on Apple’s toes – it had already sued Digital Research over the quite Mac-like GEM Desktop. So, Windows 95 didn’t have drive icons on the desktop – they lived inside a virtual folder called “My Computer” instead. Another virtual folder, “Network Neighborhood”, showed visible file servers and let the user browse for share volumes using the Explorer UI. The whole Explorer desktop lived in a single Windows process: so, if you started a long file operation, such as copying files to an external drive, you couldn’t do anything else. The whole desktop locked up for as long as the dialog box with the progress bar was visible.

For one awkward year, Microsoft’s two separate and independent OS product lines had very different UIs. The first release of Windows NT was called “Windows NT 3.1”, keeping it in harmony with the existing DOS-based Windows 3.1. For a first release, it was remarkably stable and reliable, but it required a formidable PC for 1993. The youthful Reg FOSS desk deployed it in production in the City of London, and to be even vaguely usable it needed a Pentium CPU and a whopping 16 MB of RAM – at the time, that meant a PC costing over £5,000 (£11,000 or $15,000 in 2026). This was followed by NT 3.5, which tightened up the code a bit and introduced the ability to store long filenames on FAT drives. Then came NT 3.51, which was smaller, faster, even more reliable, and also supported PCMCIA cards, file compression on NTFS, and hardware-accelerated OpenGL.

But all NT 3.x versions still had the old-fashioned GUI from Windows 3 and OS/2 1.x, with a separate “Program Manager” for launching programs and “File Manager” for handling media. After Windows 95, this suddenly looked very dated. This vulture ran it at work, and it was rock-solid and quick once we manually defined a few hotkeys for launching applications. (We used Ctrl+Alt+W for Word, Ctrl+Alt+E for Excel, Ctrl+Alt+F for File Manager, and Ctrl+Alt+D for a Command Prompt – which still used the old MS-DOS icon. “D” for DOS, you see, even if it didn’t involve actual DOS at any point.)

Windows NT 4 fixed this: a small team ported the Explorer UI from Windows 95 over to the NT kernel, although not without some effort thanks to NT’s native Unicode support. The Explorer got a few adjustments: rather than storing the Start menu entries in a single folder tree with shortcuts, it merged two trees, one for the current user and one containing entries from the global “All Users” tree.

This gave users with a high-end PC the best of both worlds: the stable and reliable NT OS, plus the fancy modern Explorer desktop. At the time, Windows 95 was still on its first release. So, it only supported the 16-bit version of the FAT filesystem, compared to which NT’s fancy journaling NTFS was much more resistant to corruption. If you had the high-end hardware on which to run it, NT 4 was a very strong proposition: modern UI combined with modern kernel and modern filesystem.

It was not without flaws. To improve the responsiveness of the new desktop, Microsoft chose to move NT’s 2D graphics rendering subsystem, the Graphics Device Interface or GDI, directly into the Windows kernel for improved performance. This eliminated an elegant aspect of the NT 3.x design, and meant that a bug in a display driver could crash the OS, introducing issues that would persist for over a decade, until the release of Windows Vista in 2007. NT 4 also didn’t include the long-promised Cairo object-based filesystem – that never shipped, although its user interface influenced the Explorer design.

NT 4 also started to date quickly. The next few releases of the DOS-based Windows family rapidly added support for several handy new tech innovations. Less than a week after the release of NT 4.0, Windows 95B, AKA “OEM Service Release 2” or OSR2, introduced FAT32. A year later, Windows 95 OSR 2.1 added support for the new USB interface. NT 4 never got those things – or at least, not official versions from Microsoft. Its Plug ’n Play support remained all but nonexistent until it was replaced by NT 5, marketed as “Windows 2000”.

Even so, NT 4 was more than good enough. It combined a solid OS core, rich server functionality, and a friendly GUI. Thirty years ago, Windows NT started to deliver on its promise. It was the beginning of the end for Novell NetWare. It also compounded Apple’s technological difficulties, leading to the company acquiring Steve Jobs’ NeXT Computer four months later. ®