Editing Windows NT 4.0 (section)

== {{anchor|Service_Packs}}Updates and service packs ==
{| border="1" class="wikitable floatright" style="font-size:85%"
! [[Service pack]] !! Release date
|-
| Service Pack 1 (SP1) || October 16, 1996
|-
| Service Pack 2 (SP2) || December 14, 1996
|-
| Service Pack 3 (SP3) || May 15, 1997
|-
| Service Pack 4 (SP4) || October 25, 1998
|-
| Service Pack 5 (SP5) || May 4, 1999
|-
| Service Pack 6 (SP6) || October 27, 1999
|-
| Service Pack 6a (SP6a) || November 22, 1999
|-
|Post SP6a Security Rollup
|July 26, 2001
|}

Windows NT 4.0 received six service packs during its lifecycle, as well as numerous service rollup packages and option packs. Only the first service pack was made available for the MIPS architecture, Service Pack 2 was the final release for the PowerPC architecture, and Service Pack 6 was the final release for the Alpha architecture. Service Pack 6a (SP6a) is the last released service pack for Windows NT 4.0. Service Pack 7 was planned at one stage in early 2001, but this became the ''Post SP6a Security Rollup'' and not a full service pack, released on July 26, 2001, 16 months following the release of Windows 2000 and nearly three months prior to the release of Windows XP.<ref>{{cite web |author=Rob Kerr |title=MS ditches Service Packs for Windows NT 4.0 |url=https://www.theregister.co.uk/2001/04/18/ms_ditches_service_packs/ |publisher=The Register |date=April 18, 2001 |access-date=September 24, 2009 |archive-date=September 29, 2010 |archive-url=https://web.archive.org/web/20100929164202/http://www.theregister.co.uk/2001/04/18/ms_ditches_service_packs/ |url-status=live }}</ref>

In addition to bug fixes, the service packs also added a multitude of new features such as [[UDMA|Ultra DMA]] mode for disk drives along with bus mastering, newer versions of [[Internet Information Services]] (IIS), user accounts and user profile improvements, smart card support, improved symmetric multiprocessing (SMP) scalability, clustering capabilities, [[MMX_(instruction_set)|MMX]] / [[3DNow!]] / [[Streaming SIMD Extensions|SSE]] / [[SSE2]] support, [[Accelerated Graphics Port|AGP]] support, [[Component Object Model|COM]] support improvements, Event Log service, [[MS-CHAPv2]] and [[NTLMv2]], [[Server Message Block|SMB]] packet signing, [[Syskey]], [[Windows NT startup process|boot]] improvements, [[Windows Internet Naming Service|WINS]] improvements, [[Routing and Remote Access Service]] (RRAS), [[Point-to-Point Tunneling Protocol|PPTP]], DCOM/HTTP tunneling improvements, IGMPv2, [[Windows Management Instrumentation|WMI]], [[Microsoft Active Accessibility|Active Accessibility]] and [[NTFS]] 3.0 support among others.<ref>{{cite web|url=http://www.microsoft.com/ntserver/nts/exec/overview/NT4SP4whatnew.asp|title=What's New in Windows NT 4.0 Service Pack 4?|website=[[Microsoft]] |date=January 12, 1999|archive-url=https://web.archive.org/web/19990117055557/http://www.microsoft.com/ntserver/nts/exec/overview/NT4SP4whatnew.asp|archive-date=January 17, 1999|access-date=August 17, 2018}}</ref>

In 1997, Microsoft released an optional update known as the "Option Pack" to add new technologies slated to be included in Windows 2000; it included IIS 4.0 with [[Active Server Pages]] (ASP), [[FrontPage Server Extensions]], Certificate Server, [[Microsoft Transaction Server|MTS]], [[MSMQ]], [[Collaboration Data Objects for Windows NT Server|CDONTS]], [[Internet Authentication Service]] (IAS), [[Windows Indexing Service|Indexing Service]], [[Microsoft Management Console]] 1.0, [[Microsoft Site Server]], [[Microsoft Transaction Server]], and [[Simple Mail Transfer Protocol|SMTP]] and [[Network News Transfer Protocol|NNTP]] services.<ref>{{Cite web |title=The NT 4.0 Option Pack |url=https://www.itprotoday.com/microsoft-windows/the-nt-4-0-option-pack |access-date=2025-03-10 |website=www.itprotoday.com |language=en}}</ref> Several features such as [[Distributed File System (Microsoft)|Distributed File System]] and [[Network Load Balancing Services|Windows NT Load Balancing Service]] (WLBS) were delivered as addons for Windows NT Server 4.0. The [[Routing and Remote Access Service]] was also a downloadable feature which replaced Windows NT 4.0's separate RAS and Multi-Protocol Routing services.

[[Internet Explorer 4]] optionally includes the "[[Windows Desktop Update]]", which integrates Internet Explorer with [[Windows Explorer]] and adds additional features to the Windows NT shell such as [[Active Desktop]].