Windows NT 3.1 was the first release of Microsoft's Windows NT operating system line. It was released in July 1993 with versions for desktop and server use. Unlike Windows 3.1, NT 3.1 was a 32-bit operating system written from scratch to be stable, secure and suitable for business use on networks and office applications. Development of NT began in 1988 with the goal of creating a successor to OS/2, but tensions with IBM led Microsoft to develop NT as a Windows clone instead.

1. Windows NT 3.1
Windows NT 3.1
Part of the Microsoft Windows family
Website: Microsoft Support Lifecycle
Windows NT 3.1 desktop Company/
Microsoft
developer:
Developer
Microsoft OS family: Windows NT
Releases Source model: Closed source
Release date 27 July 1993 Latest stable
3.10.528 SP3 / November 10, 1994
Current version 3.10.528 SP3 (10 November 1994) release:
Source model Closed source Kernel type: Hybrid kernel
License Microsoft EULA
License: Microsoft EULA
Kernel type Hybrid kernel
Support status Unsupported as of December 31,
Working state:
2000
Unsupported as of 31 December 2000

2. Windows NT 3.1 is the first release of Microsoft's Windows NT line of server
and business desktop operating systems, and was released to manufacturing on July 27,
1993. The version number was chosen to match the one of Windows 3.1, the then-latest
GUI from Microsoft, on account of the similar visual appearance of the user interface.
Two editions of NT 3.1 were made available, Windows NT 3.1 and Windows NT
Advanced Server.
It could run on Intel x86, DEC Alpha, and MIPS R4000 CPUs.
development of Windows NT started in November 1988, after Microsoft hired a group
of developers from Digital Equipment Corporation led by Dave Cutler. Many elements of
the design reflect earlier DEC experience with VMS and RSX-11. The operating system
was designed to run on multiple instruction set architectures and multiple hardware
platforms within each architecture. The platform dependencies are largely hidden from
the rest of the system by a kernel mode module called the HAL.
Windows NT was originally intended to be OS/2 3.0, the third version of the operating
system developed jointly by Microsoft and IBM. When Windows 3.0 was released in
May 1990, it was so successful that Microsoft decided to change the primary application
programming interface for the still-unreleased NT OS/2 (as it was then known) from an
extended OS/2 API to an extended Windows API. This decision caused tension between
Microsoft and IBM, and the collaboration ultimately fell apart. IBM continued OS/2
development alone, while Microsoft continued work on the newly-renamed Windows
NT.
The first public demonstration of Windows NT, at the time called "Windows Advanced
Server for Lan Manager", was at a developer conference in August 1991, and was
formally announced at the Spring 1993 Comdex in Atlanta, Georgia.
Application programming interfaces in Windows NT are implemented as subsystems
atop the undocumented Native API; it was this that allowed the late adoption of the
Windows API. Windows NT was the first operating system to use Unicode internally.
The project had a codename of just "NT OS", which is preserved in the filename of the
Windows NT kernel, ntoskrnl.exe. Since it was targeted to become the next version of
OS/2, a more official name of the project was "NT OS/2". This name is preserved up to
now in some Windows NT DDK files.
Though "NT OS/2" was finally released as "Windows NT", it is largely compatible with
OS/2 applications and HPFS disk volumes.
Originally the OS was targeted at the Intel i860 CPU, codenamed N10 (or "N-Ten").
However, the i860 was "horribly behind schedule", so the NT team used an emulator
before i860 prototype hardware (code-named Dazzle) was available. Support for the other
platforms followed later. The rationale for targeting the i860 first was to improve
portability and avoid producing an x86-centric design.

3. Windows NT 3.1
The first version of Windows NT (New technology) was released as client and Advanced
server operating system version 3.1 for Intel x86 and Mips R4000 architecture in May
1993. It is the indirect successor of Windows 3.0 and OS/2 2.0 in the new NT product
line and fulfils the requests for a stable operating system for reliable use of applications
in networks. It is suitable as network client and for applications in the Office area. The
system structure build on a microkernel, can address at most 64 mbyte RAM and
supports NTFS and FAT 16 file systems. The protected memory area secures the stable
application system, a weakness is the bad integration of new hardware in this Windows
version because no Plug and Play is supported.
Windows NT 3.1 was the first version of Windows NT. The version number 3.1 came
about because the UI was a clone of Windows 3.1 and because it conveniently "one
upped" IBM's OS/2 version 2.1 that was shipping at the time.
Unlike Windows 3.1, Windows NT 3.1 was a 32-bit operating system written from the
ground up. Originally the core of Windows NT was to be a replacement core for OS/2
version 2, but IBM did their own re-write of OS/2 without Microsoft. Microsoft instead
took what they had written and turned it in to a clone of their existing Windows product.
The Windows NT 3.1 boot logo. This version bears a greater resemblance to the
Windows 3.1 logo than later NT boot logos.
Development
Development of Windows NT started in November 1988, after Microsoft hired a group of
developers from Digital Equipment Corporation led by Dave Cutler. Many elements of
the design reflect earlier DEC experience with VMS and RSX-11. The operating system
was designed to run on multiple instruction set architecture and multiple hardware
platforms within each architecture. The platform dependencies are largely hidden from
the rest of the system by a kernel mode module called the HAL.
Windows NT was originally intended to be OS/2 3.0, the third version of the operating
system developed jointly by Microsoft and IBM. When Windows 3.0 was released in
May 1990, it was so successful that Microsoft decided to change the primary application
programming interface for the still-unreleased NT OS/2 (as it was then known) from an
extended OS/2 API to an extended Windows API. This decision caused tension between
Microsoft and IBM, and the collaboration ultimately fell apart. IBM continued OS/2
development alone, while Microsoft continued work on the newly-renamed Windows
NT.

4. The first public demonstration of Windows NT, at the time called "Windows Advanced
Server for LAN Manager", was at a developer conference in August 1991 and the product
was formally announced at the Spring 1993 Comdex in Atlanta, Georgia.
Application programming interfaces in Windows NT are implemented as subsystems
atop the undocumented Native API; it was this that allowed the late adoption of the
Windows API. Windows NT was the first operating system to use Unicode internally.
Windows NT introduced the Win32 API a 32-bit implementation of the 16-bit Windows
API. Most 16-bit Windows applications could be ported to the new system with minimal
changes and a recompile. Win32 also provided native API support for many new
features, such as networking and multithreading.
The project had a codename of just "NTOS", which is preserved in the filename of the
Windows NT kernel, ntoskrnl.exe. Since it was targeted to become the next version of
OS/2, a more official name of the project was "NT OS/2". This name is preserved up to
now in some Windows NT driver development kit files.
System support
NT was designed from the ground up to be portable to other platforms. All kernel and
subsystem code was written in C and C++. Any differences in core hardware architecture
that could not be resolved by a simple recompile (e.g., memory architecture,
multi/uniprocessor support) were offloaded to the HAL.
Also, NT's boot architecture borrowed heavily from the ARC initiative, particularly on
non-x86 platforms.
i860
Originally, NT was targeted at the Intel i860 CPU, codenamed N10 (or "N-Ten").
However, the i860 was "horribly behind schedule", so the NT team used an emulator
before i860 prototype systems designed in-house (code-named Dazzle) was available.
Support for the other platforms followed later and no public release of NT for i860
systems was made. The rationale for targeting the i860 first was to improve portability
and avoid producing an x86-centric design.
x86
NT 3.1 supported the Intel x86 32-bit family (80386 and later). Compared to 16-bit
Windows 3.x, NT's driver support was somewhat limited, but most 386 and 486
machines could run NT at least minimally.

5. MIPS
Windows NT also supported the MIPS R4000 processor; specifically MIPS systems
following the Advanced RISC Computing (ARC) specification.
Alpha
Early in the NT beta cycle, support was added for the DEC Alpha processor. However,
because the Alpha itself was not released, Microsoft's developers did not have access to
production Alpha machines to develop on until shortly before NT shipped. Consequently,
NT did not initially ship with Alpha support out of the box: the first packages of NT
included a mail-in coupon to receive a free CD of NT 3.1 with Alpha support.
Application compatibility
16-bit Windows
Windows NT provided a 16-bit compatibility subsystem, called "Windows on Windows"
(aka WOW), which allowed most Windows 3.x applications to run unmodified on NT.
Applications which made direct access to hardware, or depended on DOS-level drivers,
were not supported.
In NT 3.1, all 16-bit applications ran within a single WOW process. This meant that a
single badly behaving 16-bit application could shut down the WOW session (and any
other 16-bit applications running). However, the operating system itself was insulated, so
the WOW process could simply be killed and restarted — a significant step forward for
Windows' stability.
32-bit Windows
NT also introduced Win32, a 32-bit implementation of the Windows API. This permitted
many 16-bit Windows applications to be recompiled for the system with minimal
changes. Win32 also allowed the growing body of 16-bit Windows programmers to
leverage their skills on the new system. The Win32 API was maintained (with some
modifications) with Windows 95 further solidifying its role as Microsoft transitioned
users off of the 16-bit platform.
Win32 is a comprehensive API, offering OS services ranging from memory management
to UI access. NT prevents all user-level applications from directly accessing hardware.
This increases system reliability, at the cost of performance. However, this also means
that virtually all Win32 applications relied exclusively on the C/C++ Win32 API; the
upshot is that porting such an application to another NT-supported system architecture
(e.g., moving from x86 NT to MIPS NT) usually required no more than a recompile
(some applications might require minor tweaking, such as if assumptions were made in
code about endianness).

6. OS/2
Though "NT OS/2" was finally released as "Windows NT", it is largely compatible with
HPFS disk volumes and the x86 version supports character-mode 16-bit OS/2
applications. Many of the OS/2 APIs (particularly NetBIOS/LANMan networking APIs)
already existed in almost identical forms in both 16-bit OS/2 and DOS/Windows, so these
were incorporated into the Win32 API. For most 16-bit OS/2 programs, minimal code
changes were necessary to recompile as NT console applications.
OS/2 and Windows also share the concept of Dynamic-Link Libraries (DLLs). Although
the implementation varies somewhat between Windows and OS/2 DLLs, this additional
similarity meant that even complex OS/2 applications could usually be converted to NT
with little change to the overall design.
POSIX
Windows NT 3.1 included a subsystem that was minimally POSIX-compatible. This was
added largely to help spur sales in US government contracts, as many government
agencies mandated POSIX compatibility for consideration.
Note that POSIX compatibility is an API-level requirement. That is, one POSIX
operating system won't necessarily be able to execute binary files compiled for a different
system, even though both are POSIX compliant. POSIX simply specifies that the source
code should compile correctly for each system.
The POSIX subsystem in NT 3.1 primarily provided support for UNIX-style file system
permissions and long filenames (including permitting filename characters that are
otherwise illegal for Windows files, and denying some that are normally legal).
Internet Explorer
Microsoft offered Internet Explorer starting with IE2, and released up to Internet
Explorer 5.0 for Windows NT 3.x. Also, a IE 1.5 supported NT, but this patch was
actually released after IE2 came out.
Editions
• Windows NT Advanced Server
• Windows NT
Networking
NT 3.1 included support for three network protocols : NBF (using the NetBEUI API),
TCP/IP, and DLC

7. NetBIOS Frames protocol
At the time of NT's release, NetBIOS Frames protocol (NBF) was the most common
protocol on Microsoft LAN Manager/IBM LAN Server networks. In NT 3.1, it was the
only supported protocol for networking with legacy LAN Manager networks, as well as
other NT systems. Using NBF, NT could participate in file/print sharing, and NT
Advanced Server could act as a Domain Controller (even sharing DC duties with OS/2
LAN Manager servers).
TCP/IP
Windows NT 3.1 was the first Windows operating system to include TCP/IP support as
standard. The TCP/IP stack used was SpiderTCP, developed by Spider Systems. This was
replaced in NT 3.5 with a new stack developed in-house.
The TCP/IP stack included WinSock and STREAMS support, but it was not supported
for networking among Microsoft LAN Manager or NT systems. Also,DHCP was not
available, so IP addresses had to be manually configured. Support for NBT, DHCP, and
WINS was added in NT 3.5.
Data Link Control
Data Link Control (DLC) was supported as a transport protocol for the purpose of
communicating with network printers, such as those using an HP JetDirect interface. It
could also be used by Microsoft SNA Server for communication with IBM mainframe
systems.
Development and History
Windows NT 3.1 was essentially a Re-Written version of OS/2, that work began on in
November 1988. OS/2 was an operating system that was developed jointly by Microsoft
and IBM.
Windows NT 3.1 originally began development as OS/2 3.0. However, that changed
when Microsoft began selling Windows 3.0. This was the very first Windows version
designed for the consumer, and it was so successful, that Microsoft changed the core API
of the then still-unreleased OS/2 3.0 from an Extended OS/2 API, to an Extended
Windows API.
IBM did not like this, as the relationship between the two companies became strained,
and eventually broke apart, leaving IBM to continue OS/2 development along, with
Microsoft taking up development of Windows NT.

8. Windows NT and OS/2 briefly battled together, before Microsoft's superior Marketing
Team gave IBM a painful lesson in how to market their products. OS/2 development was
subequently discontinued.
Windows NT 3.1 was ultimately designed as a replacement for OS/2. Unlike Windows
3.1, Windows NT 3.1 was written from the ground up as a Pure 32-Bit System, although
still retaining 16-Bit support for Win16 MS-DOS and Windows Executables.
It took nearly 5 years for Windows NT's first version to be released. On July 23rd 1993,
Windows NT 3.1 finally shipped.
Timeline
• First Beta Testing of Windows NT 3.1 Beta 1, begins October 12 1992
• Windows NT 3.1 Beta 2 begins March 8 1993.
• Windows NT 3.1 Beta 3 begins June 9 1993.
• Windows NT 3.1 was Released to Manufacturing (RTM) July 26 1993.
• Windows NT 3.1 was Released on 3.5" disks August 1993.
• Windows NT 3.1 Service Pack 1 released October 1993.
• Last known for Service Pack for Windows NT 3.1 was Sp3, released October
1994.
System Requirements
• CPU: 386 or 486/25MHz
• RAM: Workstation 12MB, Server 16MB
• CD-ROM, 1.44MB or 1.2MB Floppy Drive or active Network Connection
• Graphics System: VGA-Level Video Support
• IDE, EIDE, SCSI or ESDI hard drive
• Free Hard Drive Space: 90MB
Different Platforms
Windows NT 3.1, to appeal to areas of the Business Community, ran on a variety of
system architectures. Intel's IA-32 Processors, the DEC Alpha, the MIPS R4000, and
Motorola's PowerPC processors, were all supported by Windows NT 3.1.
Released Versions
Windows NT 3.1 Product List

9. Windows NT 3.1 Product List: Workstation | Advanced Server
Service Packs
Complete Microsoft Windows Service Pack List
Complete Microsoft Windows Service Pack List:
Windows 95: SP1
Windows 98: SP1
Windows NT 3.1: SP1 | SP2 | SP3
Windows NT 4.0: SP1 | SP2 | SP3 | SP4 | SP5 | SP6 | SP6a
Windows 2000: SP1 | SP2 | SP3 | SP4
Windows XP: SP1 | SP2 | SP3
Windows Server 2003: SP1 | SP2
The Number 3.1
The Number 3.1 was used for three reasons. First off, the UI was a clone of Windows 3.1.
Secondly, Windows NT 3.1 conveniently one-upped OS/2 2.1 that shipped earlier, and
lastly, Windows NT 3.1 gave a more 'Stable' appearance than Windows NT 3.0.

10. The NT Designation
There has been much speculation over what the 'NT' name actually means. In 1998, it
was revealed that 'NT' originally meant 'New Technology', but now it just serves as an
acronym with no meaning.
Windows 2000 was originally known as Windows NT 5.0, but Microsoft dropped NT
from its name. In Hindsight, with Windows XP on the scene, the removal of NT could be
seen as an early hint that the Windows NT and 9x product lines were to Merge. But, it
was also believed that Microsoft and Nortel were involved in a Trademark dispute over
NT, so Microsoft could have removed NT to avoid further hassle.
Differences compared to Windows 3.1
Most of the accessories and applications in Windows NT 3.1 are 32-bit ports of the
Windows 3.1 versions, although some stayed 16-bit, and ran using the Windows 3.1
Emulation subsystem. Perhaps one of the biggest improvements to Windows NT,
compared to other versions, was it's internal use of Unicode, as opposed to most others
using ANSI.
Microsoft Operating System Versions
Microsoft Operating System Versions:
MS-DOS: QDOS | 1.0 | 2.0 | 2.1 | 2.11 | 3.0 | 3.1 | 3.2 | 3.21 | 3.3 | 3.3A | 3.31 | 4.0 | 4.01 | 4.01A |
5.0 | 5.0A | 6.0 | 6.2 | 6.21 | 6.22 | 7.0 | 7.1 | 8.0
Windows 1.x: 1.0 | 1.01 | 1.02 | 1.03 | 1.04
Windows 2.x: 2.0 | 2.01 | 2.1 | 2.2
Windows 3.x: 3.0 | 3.0A | 3.1 | 3.11 | 3.2
Windows for Workgroups 3.x: 3.1 | 3.11
Windows 9x: 95 | 98 | ME
Windows NT: 3.1 | 3.5 | 3.51 | 4.0 | 2000 | XP | 2003

11. Future Windows NT: Vista | Longhorn Server | Blackcomb Server
Windows CE: 1.0 | 1.1 | 2.0 | 2.1 | 2.11 | 2.12 | 3.0 | 4.0 | 4.1 | 4.2 | 5.0
Windows Embedded: NT | XP
Windows Mobile: 2003 | 5.0
Previous Windows Codenames: Janus | Snowball | Kato | Daytona | Chicago | Memphis |
Millennium | Cairo | Odyssey | Neptune | Whistler | Longhorn | Blackcomb
Screenshots
Windows NT 3.1 - The interface looks like the
same of Windows 3.11
Windows NT 3.1 - special Administration
and RAS programs are part of the
standard in Windows NT
Windows NT 3.1 - the user manager is for the
creation and management of user profiles

12. Windows NT 3.1 - a backup program of
Microsoft is also include
Windows NT 3.1 - The system control has
6 icons more compared with Windows
3.11, these are: system, network, servers,
services, devices and UPS
Windows NT 3.1 - Server services like the
logging running in the background and
provide a smooth process

13. Windows NT 3.1 - The system variables of NT
have remained uniform for all Windows NT
versions up to this day
Windows NT 3.1 - Deadlocked programs can
be killed controlled now without endangering
the operating system
The NT 3.1 Program Manager. Aside from
being user-aware it works like the Windows 3.1
program manger. The Program Manager
window contains a number of program groups,
each of which may contains a number of
program items which, when double-clicked, will
launch the application specified by the
properties of the program item. Most of the
accessories and applications are 32-bit ports of
the Windows 3.1 versions, although some
stayed 16-bit and run using the Windows 3.1
emulation subsystem.

14. The NT 3.1 about box with the boot logo set as
the desktop background.
The NT 3.1 File Manager. Again, this is similar to
the Windows 3.1 file manager, but with a few NT
specific features such as the "security" menu item
to control file permissions.
With NT 3.1, as with Windows 3.1, video
settings were made through the GUI version of
the Setup program.
Windows NT 3.1 also includes 32-bit versions of
all of the multimedia components included with
Windows 3.1.
Finally, shutting down Windows NT 3.1.