Windows NT 4.0 was a graphical, business-oriented operating system released by Microsoft in 1996 as the successor to Windows NT 3.51. It had a more stable kernel than Windows 95 but required more memory and had less support for plug-and-play hardware. It included the Windows 95 user interface and applications as well as new features like Internet Information Services and Microsoft Transaction Server. Support for Windows NT 4.0 ended in 2004 due to major security vulnerabilities that could not be fully addressed.

1. 4.0

2. Developer: Microsoft Releases: Release date RTM: 31 July 1996 Retail: 24 August 1996 ( info ) Current version 4.00 Service Pack 6a (SP6a) (Build 1381)(4.0.1381) (1999-11-30; 9 years ago) ( info ) Source model: Closed source License : MS-EULA Kernel type: Hybrid Platform support: IA-32 , Alpha , MIPS , PowerPC Support status: Unsupported as of 30 June 2004 for Windows NT 4.0 Workstation and 31 December 2004 for Windows NT 4.0 Server

3. Windows NT 4.0 is a preemptive , graphical and business-oriented system designed to work with either uniprocessor or symmetric multi-processor computers. It was the next release of Microsoft 's Windows NT line of operating systems and was released to manufacturing on 31 July 1996 (public release on 24 August 1996). It is a 32-bit Windows system available in both workstation and server editions with a graphical environment similar to that of Windows 95 . The "NT" designation in the product's title initially stood for "New Technology" according to Microsoft's then-CEO Bill Gates , but now no longer has any specific meaning. Windows NT 4.0 was succeeded by Windows 2000 in February 2000. Windows NT 4.0 is classified as a hybrid kernel operating system .

4. While providing much greater stability than Windows 95, it was also less flexible from a desktop perspective. Much of the stability is gained by the use of protected memory and the hardware abstraction layer. Direct hardware access was disallowed and "misbehaving" applications were terminated without needing the computer to be restarted. The trade-off was that NT required an excessive amount of memory in comparison to consumer targeted products such as Windows 95. Overview

5. Windows NT 4.0 is also less user-friendly than Windows 95 when it comes to certain maintenance and management tasks; there is, for instance, no support by default for " Plug and play " (although limited support could be installed later) which greatly simplifies installation of hardware devices or support for USB devices. Many basic DOS applications would run however graphical DOS applications would not run due to the way they accessed graphics hardware. Windows NT 4.0 is also less user-friendly than Windows 95 when it comes to certain maintenance and management tasks; there is, for instance, no support by default for " Plug and play " (although limited support could be installed later) which greatly simplifies installation of hardware devices or support for USB devices. Many basic DOS applications would run however graphical DOS applications would not run due to the way they accessed graphics hardware.

6. The difference between the NT and "9x" lines of Windows ended with the arrival of Windows XP , by which time the gaming APIs—such as OpenGL and DirectX —had matured sufficiently to be more efficient to write for than common PC hardware and the hardware itself had become powerful enough to handle the API processing overhead acceptably. Windows NT 4.0 is the last major release of Microsoft Windows to support the Alpha , MIPS or PowerPC CPU architectures. It remained in use by businesses for a number of years, despite Microsoft's many efforts to get customers to upgrade to Windows 2000 and newer versions. It was also the last release in the Windows NT line to use the "Windows NT" name.

7. Feature The most noticeable difference from Windows NT 3.51 is that Windows NT 4.0 has the user interface of Windows 95 , including the Windows Shell , Windows Explorer (known as Windows NT Explorer), and the use of "My" nomenclature (e.g. My Computer ). It also includes most applications introduced with Windows 95

8. The server editions of Windows NT 4.0 include a built-in web server , Internet Information Services version 2.0. It also natively supported plugins and extensions of Microsoft FrontPage , a web site creation and management application. Other important features included with this release were Microsoft Transaction Server for network applications, and Microsoft Message Queuing (MSMQ), which improved communication.

9. One significant difference from previous versions of Windows NT is that the Graphics Device Interface (GDI) is incorporated into the kernel to speed up the graphical user interface (GUI), resulting in a significant performance improvement over Windows NT 3.51 and also creating the requirement to have graphics drivers located in the kernel, resulting in potential stability issues. It was the first release of Microsoft Windows to include DirectX as standard -- version 2 shipped with the initial release of NT 4.0, and version 3 was included with the release of Service Pack 3 in mid-1997. Unlike Windows 95 (which didn't include DirectX until the OSR2 release in August 1996), Windows NT 4.0 does not support Direct3D , and hardware-accelerated graphics were not available. Later versions of DirectX were not released for NT 4.0, but various hacks to provide DirectX 5 and 6 support in NT 4.0 have circulated around the Internet.

10. Windows NT 4.0 also included a new Windows Task Manager application. Previous versions of Windows NT included the Task List application, but it only shows applications currently in memory. To monitor how much CPU and memory resources are being used, users were forced to use Performance Monitor. The task manager offers a more convenient way of getting a snapshot of all the applications running on the system at any given time. Microsoft offered up to Internet Explorer 6.0 SP1 for NT 4.0, provided it was updated to handle it.

11. Service Packs Microsoft released Windows NT 4.0 service packs primarily to fix bugs . Windows NT 4.0, during the product's lifecycle, had several service packs, as well as numerous service rollup packages and option packs. The last full service pack was Service Pack 6a (SP6a). A SP7 was planned at one stage in early 2001, but this became the Post SP6a Security Rollup and not a full Service Pack, released on 26 July 2001, 16 months after Windows 2000 and nearly three months prior to Windows XP.

12. The service packs and an option pack were also released to add features. These included newer versions of Internet Information Services , versions 3.0, and 4.0, support for Active Server Pages , public-key and certificate authority functionality, smart card support, improved symmetric multiprocessing (SMP) scalability, clustering capabilities, and component object model (COM) support, among others.

13. Security Microsoft stopped providing security updates for Windows NT 4.0 Workstation on 30 June 2004 and Windows NT 4.0 Server on 31 December 2004, due to major security flaws including Microsoft Security Bulletin MS03-010 , which according to Microsoft could not be patched without significant changes to the core operating system. According to the security bulletin, "Due to [the] fundamental differences between Windows NT 4.0 and Windows 2000 and its successors, it is infeasible to rebuild the software for Windows NT 4.0 to eliminate the vulnerability. To do so would require rearchitecting a very significant amount of the Windows NT 4.0 operating system, and there would be no assurance that applications designed to run on Windows NT 4.0 would continue to operate on the patched system."

14. Between June 2003 and June 2007, 127 security flaws were identified and patched in Windows 2000 Server, many of which may also affect Windows NT 4.0 Server; however, Microsoft doesn't test security bulletins against unsupported software. Because of this, Microsoft is recommending current Windows NT customers to upgrade to a supported operating system such as Windows Server 2003, or Windows Server 2008 .