Windows NT 3.5

Windows NT 3.5 Windows NT 3.51 Windows NT 4.0 Windows 2000 Windows XP Windows Server 2003 Windows XP Professional x64 Windows Vista Windows Server 2008 Windows 7 Windows Server 2008 R2 Windows 8 Windows Phone 8 Windows RT Windows Server 2012

Windows NT 3.5 is an operating system from Microsoft and the successor to the Windows NT version 3.1.


Already towards the end of the development of its predecessor Microsoft Windows NT 3.1, collected the developers ideas that could not be implemented at this stage of the development cycle and thus were planned for the next version, which should be published in the fall of 1994.

David N. Cutler knew that the first version of a product is never perfect. Inspired by the numerous criticisms of Windows NT 3.1, he wanted to start with the development of the successor immediately. However, meant that it was competing with Cairo, a new project from Microsoft under the leadership of Jim Allchin. Windows NT should be integrated together with the development team in the Cairo project and so continue development under a new leadership. Cutler did not accept this decision and left the development team. Bill Gates feared that Cutler would leave the company completely, and tried to persuade him to stay. Cutler finally accepted this by jointly developed both projects and the new leadership regarded merely as a formality.

For the new operating system, the development team set three broad goals. The first goal was performance, because Windows NT 3.1 was widely regarded as too slow. The very high hardware requirements of the predecessor should be reduced and the performance of the operating system are optimized, which was achieved primarily through the use of improved compiler. In June 1994, Microsoft reported a four to eight megabytes less memory consumption compared to its predecessor as well as 50 to 100 percent faster graphics display and 20 to 30 percent faster file access.

The second objective was NetWare compatibility. Although Novell promised a NetWare Client for Windows NT, the delivery hesitated but also repeated. So Microsoft finally decided to develop its own NetWare client and be shipped with Windows NT 3.5. The development team knew that Windows NT would have no chance in the market, if it would offer no way to connect to NetWare networks.

The third objective was compression. Due to the growing demand for disk space programs like Double Space in MS- DOS were widespread. Windows NT 3.5 should support a similar technology.

Another developer focused their attention on the TCP / IP protocol stack. The protocol stack included with Windows NT 3.1 was licensed from a third party called Spider system. Its code was based on the STREAMS programming used in Unix. This STREAMS had to be ported to Windows NT, which had a negative impact on performance. Windows NT 3.5 should therefore include a new, proprietary TCP / IP protocol stack.

Getting information about a successor to Windows NT 3.1, codenamed Daytona came out in December 1993. In February 1994, the development was officially announced at WinHEC in February 1994. End of March, followed by the first public presentation of the new operating system.

The final version of NT 3.5 was released on 13 September 1994. On 13 January 1995, the first service pack came out, which provided, among other things, a method to override the Pentium FDIV bug. The Service Pack 2 was followed on 1 March 1995. On August 29 Finally, in 1995, Service Pack 3 was completed.


The two versions have been renamed in contrast to NT 3.1 and Windows NT 3.5 Workstation hot now, and Windows NT 3.5 Server. While there are still 3.1 were hardly differences between the workstation and the server version in Windows NT, the two versions of Windows NT 3.5 are clearly demarcated. Windows NT 3.5 Workstation accepts only 10 client connections, so that a use as a server apart from small networks is excluded.

Windows NT 3.5 Workstation was available for 319 USD. With Windows NT 3.5 Server that is still valid today licensing model from Microsoft has been introduced, in which a license is to buy for each client that accesses the server. Cost the previous version of the server, there is a flat rate $ 1,495, no matter how many clients were connected, the price was now at 699 USD, provided 39 USD had to be paid for each client.

Windows NT 3.5 Server was first marketed not only individually, but also under the name Microsoft BackOffice together with numerous programs, such as a mail server and a SQL server.


Compared with the previous several improvements have been made. So now it is possible to have 16 -bit Windows programs run in separate environments to allow preemptive multitasking between them and to prevent a faulty 16- bit application can crash all other 16 - bit applications. There is also a new option to lock an account for a certain period of time if the password is entered too many times incorrectly.

To adjust the screen resolution and color depth is no longer the old Windows setup program, but the new system control option used in Windows NT 3.5 display. This makes it possible to test the selected options involved in advance by a test image is displayed, if the graphics card drivers support this. To support further the development of graphics software was added in Windows NT 3.5, a licensed by Silicon Graphics OpenGL graphics library. To demonstrate the operating system stood at some screen savers.

The newly developed VFAT allows long file names now also available on FAT partitions, which were still restricted under the predecessor NT 3.1 to the 8.3 format. Because of these changes and other changes to the NTFS file system must, if Windows NT 3.1 and Windows NT to be 3.5 run on one machine in parallel, an update from the Windows NT 3.5 CD installed to Windows NT 3.1 to access these partitions allow.

Windows NT 3.5 includes a revised TCP / IP protocol stack which was programmed from scratch. Windows NT 3.5 supports DHCP and contains a name resolution service called WINS. A supplied NetWare client provides access to NetWare networks with on-board means, without need of installing any additional software for the first time. The Remote Access Service, which only enabled access to resources NetBEUI on Windows NT 3.1, now supports TCP / IP and IPX, so for instance, can also be accessed on NetWare shares. In this context, RAS supports a connection through PPP and SLIP.

The server version of Windows NT 3.5 includes some new features. It offers the possibility to act as a NetWare gateway. So DOS and Windows clients can access resources on a NetWare server, without having to communicate directly with the network. A program designed to help migrate a NetWare server along with its data, such as directories and users on Windows NT Server. Other computers on the network can be started remotely from the server, which is primarily intended for diskless workstations. The remote access server no longer supports 64, but 256 incoming remote access connections.

The driver library has been significantly expanded compared to its predecessor, the PCI bus is now supported as well as modern ATAPI CD- ROM drives.


The system requirements have not changed 3.1 compared to its predecessor Windows NT. For installation on x86 systems, a 80386 processor at 25 MHz, at least 12 MB ​​RAM, 75 MB hard disk space VGA graphics card were needed. RISC systems required instead 16 MB RAM and 92 MB hard disk space, and a CD - ROM drive. Unlike its predecessor, Windows NT 3.5 can not be installed on the 80386 -based multi-processor systems.

The installation of Windows NT is possible either from the CD- ROM that accompanied three boot disks, or on x86 machines from a disk set (consisting of 21 3.5 "diskettes ). It is also possible, an existing Windows NT 3.1. refresh

Due to a bug in the processor identification to install the operating system on all processors since the Pentium II fails This problem was never fixed from Microsoft, but unofficial patches are available to allow the installation.


The reports from Microsoft Windows NT 3.5, which is faster than its predecessor, were confirmed: the same benchmarks running under NT 3.5 faster than under NT 3.1, measured yielded an increase in performance by up to 100 percent. The operating system has sold better than its predecessor, which is due according to analysts not alone on the improvements of the new version, but also on marketing mistakes of the competition. It is estimated that early 1995 400.000 141.000 workstations and servers running Windows NT. In the face of improvements in the migration of existing systems went with Windows NT 3.1 to the new version progressed speedily. For Microsoft, the success of the new version came as a surprise, the operating system was partially sold. The range of 32 -bit Windows applications improved, so there was at the time about 1,200 applications. Even Microsoft itself supported operating system with 32- bit versions of Microsoft Word and Microsoft Excel.

Of the systems sold with Windows NT amounted to RISC systems only five percent. The attempt by DEC to establish computer with Alpha processors using Windows NT as a desktop PC, failed, so the company focused on the high- end market, in order to find a niche. Both DEC and NEC, which computer sales with MIPS architecture, hoped by the improved operating system a new feed.

Originally Windows NT 3.5 should also provide support for the PowerPC architecture. However, IBM had to postpone repeated delivery of the PowerPC processors, so they decided that PowerPC support is not for NT nachzuliefern 3.5, as was done with the Alpha AXP version of Windows NT 3.1, but a revised version of Windows NT 3.5 publish under the name Windows NT 3.51. This is not least due to the large number of known errors, the Windows NT 3.5 contained.