List of Microsoft codenames

# A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

#

286DOS
OS/2 1.0, Microsoft naming
6 on 6
Windows Mobile 6.1.4

A

ADOS
OS/2 1.0
Advanced Windows
The original announced name for NT-based Windows, see Razzle
Akebono
Xbox Controller S
Alder
Windows CE 1.0
Anaconda
Xbox Series X
Andromeda
Canceled phone variant of Windows Core OS
Surface Pocket (cancelled Surface model designed to run Andromeda OS)
Another Fucking Driver
Ancilliary Function Driver (afd.sys)[1]
Application Framework eXtensions
Microsoft Foundation Class Library
Apollo
Windows Phone 8
Arcata
Surface Pro 9 (5G)
Aruba
Surface Hub OS; see Lhok Sukon (LSX)
Argo
Zune
Asteroid
Windows 2000 Service Pack 1
Astro
MS-DOS 6
Canceled Microsoft Lumia phone model. Utilized a Qualcomm Snapdragon 820 (MSM8996) SoC.
Athens
Windows 10 IoT Core; named after the capital city of Greece
Aurora
Windows Small Business Server 2011 Essentials
Avalon
Windows Presentation Foundation

B

Blackcomb
Planned successor of Windows XP and later Longhorn/Vista; named after Whistler Blackcomb, a ski resort in British Columbia popular among Microsoft executives
Birch
Windows CE 2.0
BirchWay
Surface Pro 9 (Intel)
Big Rock
Surface Laptop 7
BlackRock
Windows Dev Kit 2023
Blue
Windows 8.1[2]
Windows Phone 8.1
Bobcat
Windows Small Business Server 2003
Bobsled
Internal name for Windows Media Center Extender devices
Breckenridge
Windows Storage Server 2008 R2 Essentials[3][4]
Brooklin
Xbox Series X refresh, scheduled to be released in 2024[5]
Bulletproof
Microsoft mail remote client[6]

C

Cairo
Canceled successor of Windows NT 3.x that aimed to implement Bill Gates' "Information at your fingertips" vision
Cairo Domains
Active Directory
Cairo Messaging
Microsoft Exchange
CairOLE
OLE 3.0
Callaway
Windows Dev Kit 2023
Cambria
Surface Pro X (SQ1)
Carina
Surface Pro X (SQ2)
Catapult
Microsoft Internet Information Server
Cascades
Canceled successor to Windows Essential Business Server 2008 based on Windows Server 2008 R2.
Cascadia
Windows Terminal; also used as the name of the Cascadia Code and Mono typefaces, designed for the Terminal
Cashmere
Word for Windows
Cassini
Windows Embedded 8[7]
Caspar
Surface Pro X (Wi-Fi)
Cedar
Windows CE 3.0
Centaurus
Surface Neo
Centro
Windows Essential Business Server 2008
Charles de Gaulle, CDG
Windows 10X
Chelan
Windows Embedded Compact 7
Cherry Hill
Windows 11 shell experience pack updated via the Store
Chicago
Windows 95
Cityman
Lumia 950 XL
Cleveland
Alternative name for a canceled successor of Windows 95, more commonly known as Nashville
CMERGE
Microsoft C 3.0, the first version of the C-branded compiler written by Microsoft (merging a separate Xenix C compiler, the backend of their Compiled BASIC product, and the licensed Lattice C Microsoft was selling for the IBM PC)
Cobalt
The 21H2 (second half of 2021) engineering semester of Windows as a service; the base for the original release of Windows 11
Colorado
Windows Small Business Server 2011
Control Program/DOS, CP/DOS
OS/2 1.0; follows IBM mainframe product naming
Copper
The late 2022 engineering milestone of Windows as a service
CorePC
Alleged successor to Windows Core OS. Provides a modular operating system base targeting different system form factors[8]
Corona
Windows Media Player 9 Series[9]
Cougar
The 32-bit DOS kernel in Windows 95 (DOS386.EXE/VMM32.VXD)
Windows Small Business Server 2008
Crescent
Windows Media Player 10
Cronos
Canceled Microsoft Surface Duo model. Utilized a Qualcomm Snapdragon 778G 5G (SM7325) SoC.
Crossbow
Windows Mobile 6.0
Cruiser
OS/2 2.0
Cupcake
Internal Windows componentization effort featuring 5 layers, related to CorePC
Cutter
OS/2 1.3

D

Darwin
Windows Installer
Daytona
Windows NT 3.5
Denali
Active Server Pages
SQL Server 2012
Deschutes
Windows 365 Cloud PC
Detroit
USB supplement update for Windows 95 OSR2
Diamond
Windows Media Center UI overhaul for Windows Vista
Dilithium
The early-2024 engineering milestone of Windows as a service. Named after the fictional material from Star Trek,[10] as arsenic is infamous for its use in poisons.
DirectX Box
Xbox
Doesn't Matterhorn
Pre-reset Windows Vista[11]
DOS 5.0
OS/2 1.0; name used primarily by Microsoft – implies that OS/2 is the successor to the multitasking MS-DOS 4.
The Duke
Xbox controller[12]
Durango
Xbox One

E

Edmonton
Xbox One S
eHome
Windows Media Center
Eiger
Windows Fundamentals for Legacy PCs
Electronic Paper
The original concept for Excel
Ellewood
Xbox Series S refresh, scheduled to be released in 2024[5]
Elmer
Surface Laptop Studio 2
Elroy
Windows Live Mail
Emerald
Windows XP Media Center Edition 2005 Update Rollup 2
Epsilon
Surface Duo (after it was decided that the device would use Android instead of the cancelled Andromeda, and it was renamed)
Ersa
Surface Laptop Studio 2
Ersa Refresh
Surface Laptop Studio 3
Escher
Visual Basic for MS-DOS
Ethos
Surface Duo
Excalibur
SQ SoC

F

Fastbike
Fast boot in Windows Neptune (Profile Accelerated Boot Accelerator)
Freestyle
Windows XP Media Center Edition
Frosting
Microsoft Plus! Companion for Windows 95
Fiji
Windows Vista Media Center TV Pack
Firesteel
Internal Windows 11 self-hosting effort
Firebird
An upcoming update for Windows 10 Team
Football
OS/2 1.0–era multiple virtual DOS machines prototype using the virtual 8086 mode (previously known as Pigskin)
Fusion
Windows Side-by-Side Component Store (WinSxS)
.NET Framework CLR Loader

G

Galileo
Windows CE 3.0
Gallium
The mid-2023 engineering milestone of Windows as a service
Game SDK
DirectX
Gandalf
Encarta Multimedia Encyclopedia (original 1993 release)[13]
Gemstar
WebTV for Windows
GeorgeTown
Surface RT[14]
GeorgeTown X
Surface Pro[14]
Germanium
The late-2023 engineering milestone of Windows as a service; the base for the Windows 11 2024 Update
Grendel
Surface Laptop 3 (AMD)
Guilin
Canceled Microsoft Lumia phone model. Utilized a Qualcomm Snapdragon 210 (MSM8909) SoC.
Gulliver
Surface Laptop Go 3

H

Haiku
Modular Windows
Harmony
Windows XP Media Center Edition 2004
Harvest
Surface Pro X (Wi-Fi)
Hobart
Surface Pro X (SQ1)
Honjo
Canceled Microsoft Lumia phone model. Utilized a Qualcomm Snapdragon 210 (MSM8909) SoC.
Honolulu
Windows Admin Center
Hudson Valley
Rumored successor of Windows 11[15]
Hydra
Windows NT Server 4.0, Terminal Server Edition

I

Idaho
Unrealized successor of Windows XP[16]
Immersive Launcher, Immersive Shell
Start screen
Impala
Windows NT Embedded 4.0
Indigo
Windows Communication Foundation
Interface Manager
Internal UI library used by the Microsoft Apps team, merged with the Graphics Device Interface to create the project that led to Windows 1.0
Iron
The 21H1 (first half of 2021) engineering semester of Windows as a service; the base for Windows Server 2022
Iris
Surface Mini

J

Jaguar
The 16-bit MS-DOS subsystem in Windows 95. A standalone retail release was also planned at one point, which ultimately ended up not materializing
Jamdani
Journal user interface in Windows Andromeda OS
Jameson
Windows CE 4.1
Janus
Combined bundle of Windows 3.1 and MS-DOS 5
Canceled 64-bit port of Windows 2000 for Itanium-based systems[17][18]
Jastro
Combined bundle of Windows 3.1 and MS-DOS 6; portmanteau of Janus and Astro
Jazz
Computer architecture based on the MIPS R4000 processor
Juneau
SQL Server 2012 Developer Tools
Jupiter
Windows CE 2.0
Windows Runtime

K

Kryptos
Xbox One[19]

L

Lancelot
Surface Laptop and Surface Laptop 2
Lhok Sukon, LSX
Surface Hub OS; internally codenamed after the airport of the same name, intended for the cancelled Surface Hub 2X[20]
Lifeboat
MS-DOS 5
Linares
Surface Thunderbolt 4 Dock
Lite
Windows 10X
Lockhart
Xbox Series S
Lonestar
Windows XP Tablet PC Edition 2005
Longhorn
Windows Vista, Windows Server 2008; named after a bar situated between the Whistler and Blackcomb mountains.

M

Macallan
Windows CE 5.0
Magneto
Windows Mobile 5.0
Manganese
The 20H2 (second half of 2020) engineering semester of Windows as a service
Mango
Windows Phone 7.5
Mantis
Windows XP Embedded
Mars
Application framework used in Activity Centers, and the Help and Support Center in Windows Me and Windows XP
McKendric
Windows CE 4.2
Memphis
Windows 98
Merlin
Pocket PC 2002[21]
Millennium
Windows Me
ModernPC
Windows 10X
MoGo
Start screen
MoSh (Modern Shell)
Windows 8 user interface
Mojave
Fictitious release of Windows that was in fact a rebranded Windows Vista, which was the subject of a Microsoft case study known as the Mojave Experiment
Monaco
Visual Studio Code; adopted as the name of the Monaco Editor, the code editor component of Visual Studio Code decoupled for use in other applications
Monad
PowerShell
Monarch
Outlook progressive web application
Monkton
Windows Dev Kit 2023
Monza
Surface Neo
MT-DOS
Multitasking MS-DOS 4

N

Nashville
Internet Explorer 4; originally referred to a canceled successor of Windows 95.
Nemesis
Windows Media Encoder 7.0[22]
Neptune
Canceled NT-based successor of the Windows 9x series; project merged with Odyssey in early 2000 to form Whistler. Sometimes stylized as NepTune.
NewShell
Shell Technology Preview; a series of updates for Windows NT 3.51 that backport the Windows 95 user interface
Nickel
The 2022 engineering milestone (also referred to as 22H2) of Windows as a service; the base for the Windows 11 2022 Update
NoDo
Windows Phone 7 March 2011 update
Northstar
Canceled Nokia Lumia model based upon the Qualcomm Snapdragon 820 (MSM8996) SoC
NT OS/2, NTOS
NT-based rewrite of OS/2 canceled in favor of Windows NT, see Razzle
NT Windows
Alternative name for Windows NT before that name was standardized, see Razzle
Nyx
Surface Pro 3

O

O'Hare
Internet Explorer 1; named after the international airport near Chicago, the codename for Windows 95.
Oasis
Windows Holographic for Hololens 2[23]
Odyssey
Unrealized successor of Windows 2000; project merged with Neptune in early 2000 to form Whistler.
Omega
Early version of Microsoft Access[24]
Omega-13
Longhorn development reset; named after the time travel device of the same name seen in Galaxy Quest's climax,[25] which sends the user exactly thirteen seconds back into the past
One Outlook
Outlook progressive web application
Opus
Word for Windows
Orca
SNA Server 3.0
OS/2 3.0
NT-based rewrite of OS/2 canceled in favor of Windows NT, see Razzle
Ozone
Windows Mobile 2003

P

Panther
A short-lived lightweight fork of the Windows NT kernel for use in a consumer 32-bit version of Windows
Windows Deployment Services - WIM-based Windows Setup
Pegasus
Windows CE 1.0
Photon
Windows Phone 7
Pigskin
OS/2 1.0–era multiple virtual DOS machines prototype using the virtual 8086 mode (early name for Football)
OS/2 2.0 (early name for Cruiser)
Pinewood
Surface Pro X
Polaris
Canceled desktop variant of Windows Core OS, intended for low-cost computers
Portable OS/2
NT-based rewrite of OS/2, see Razzle
Porthole
Windows Libraries for OS/2[26]
Portico
Windows Phone 8 GDR1
Protogon
ReFS

Q

Quartz
ActiveMovie
Q, Quattro
Windows Home Server
Quebec
Windows Embedded Standard 7

R

Rapier
Pocket PC 2000[27]
Razzle
Windows NT 3.1; originally a rewrite of OS/2 based on the new NT kernel design, which was canceled with the IBM-Microsoft split in favor of Windows NT; kept as the name of the Windows NT build environment
Ren
Outlook;[28] named after the fictional chihuahua cartoon character of the same name from The Ren & Stimpy Show
Redstone
Windows 10 Anniversary Update through October 2018 Update; named after the reactive mineral from Minecraft.
Reunion
Windows App SDK

S

Saana
Lumia 650
Saimaa
Lumia 550
Salta
Surface Laptop SE
Santa Rosa
Surface Pro X (SQ2)
Santorini (JTR)
Operating system intended to run on the Surface Neo; internally codenamed after the airport of the same name
Scarlett
Xbox Series X/S
Scorpio
Xbox One X
Sebile
Xbox Universal Controller, scheduled to be released in 2024[5]
Shell Update Release
Windows NT 4.0
Sherlock
Dr. Watson
Sizzle
A collection of changes intended to improve overall OS/2 performance
Slate
Microsoft Management Console
Sloop
OS/2 1.2
Small Business Server "8"
Windows Server 2012 Essentials
Snowball
Windows for Workgroups 3.11
Solution Server
Windows MultiPoint Server 2010
Sparta
Windows for Workgroups 3.1
Spartan
Microsoft Edge
Sphinx
SQL Server 7.0
Spring '14, S14
Windows 8.1 Update 1
Stimpy
Windows 95 shell and user interface
Outlook;[28] named after the fictional cat cartoon character of the same name from The Ren & Stimpy Show
Sundown
64-bit Windows NT (Win64);[29] named as a jab at Sun Microsystems, as Solaris would be one of the main competitors in the 64-bit operating system market[30]
Sun Valley
Windows 11
Suzuki
Surface Pocket (cancelled Surface model designed to run Andromeda OS)
Sydney
Bing Chat / Copilot
Symphony
Windows XP Media Center Edition 2005

T

Take Home
Windows Media Center internal dogfooding effort
Talisker
Windows CE 4.0
Talkman
Lumia 950
Tango
Windows Phone 7.5 July 2012 update
Tarantula
IIS for Windows 95[31]
Tenjin
Surface Laptop SE
The Fucking Clown
Office Assistant[32]
Thunder
Visual Basic 1.0[33]
Titanium
Windows Mobile 6.5
Titanium
The 19H1 (first half of 2019) engineering semester of Windows as a service; the base for the Windows 10 May 2019 Update
Trimaran
OS/2 1.1
Triton
Planned minor update for Neptune
Tukwila
Unofficial codename for Windows NT 4.0 coined by Dave Cutler; named after a town in the neighborhood of Seattle to poke fun at Cairo
Threshold
Windows 10; named after an in-game location from Halo: Combat Evolved. Also called Windows 8.2 in some places.
Tuva
Nano Server

U

Utopia (Home)
Microsoft Bob

V

Valo
Surface Pro 9 (5G)
Vanadium
The 19H2 (second half of 2019) engineering semester of Windows as a service; the base for the Windows 10 November 2019 Update
Vibranium
The 20H1 (first half of 2020) engineering semester of Windows as a service; the base for the Windows 10 May 2020 Update and later. Named after the fictional mineral from Marvel Comics to prevent confusion with the open source Chromium project
Vienna
Short-lived name for Blackcomb after a 2006 rename; the name was supposed to start a new set of codenames derived from popular cities and locations known for their "vistas".[34]
Viper
Unknown early NT selfhosting effort
Vail
Windows Home Server 2011
Viridian
Hyper-V[35]

W

Whistler
Windows XP, Windows Server 2003; named after Whistler Blackcomb, a ski resort in British Columbia popular among Microsoft executives
Winball
Windows for Workgroups 3.1
Window Manager
Windows 1.0
Windows 7
Windows 7; coined by incrementing the version number of Windows Vista (6.0) by one
Windows 8
Windows 8
Windows NT 3.99
Internal effort to advocate for smaller and more easily achievable NT releases
Windows NT 5.0
Windows 2000; not a codename per se—according to a member of the development team, "Jim Allchin didn't like codenames."[36]
Windows Presentation Foundation/Everywhere
Silverlight
WMS 2
Windows MultiPoint Server 2011
WMS 3
Windows MultiPoint Server 2012
Wolverine
TCP/IP-32 stack for Windows for Workgroups 3.11
Wren
Outlook; originated from Bill Gates mistaking Ren, the proper codename, for Christopher Wren, the architect of St. Paul's Cathedral.[28]

X

Xenon
Xbox 360
Hyper-V containerization system introduced in Windows Server 2016

Y

Yamazaki
Windows CE 6.0
Yilan
Surface Go 4
Yushan
Surface Laptop Go 3

Z

Zaca
Surface Pro 9 (Intel)
Zamboni
Visual C++ 4.1[37]
Zeta
Surface Duo 2
Zinc
The early 2023 engineering milestone of Windows as a service; the base for the Windows Server, version 23H2 and Azure Stack HCI, version 23H2

References

  1. Chen, Raymond. Microspeak: FCIB, The Old New Thing. 14 November 2017.
  2. Windows Blue Vision
  3. Garcia, Joel. Announcing Windows Storage Server 2008 R2 Essentials, Windows Storage Server Blog. 8 November 2010.
  4. Jo Foley, Mary. There's another new Windows Server in the Microsoft pipeline, ZDNET. 2 November 2010.
  5. 5.0 5.1 5.2 Warren, Tom. This is Microsoft’s new disc-less Xbox Series X design with a new gyro controller, The Verge. 19 September 2023.
  6. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  7. Microsoft. Windows Embedded Standard 8 CTP3 Release Notes, Windows Embedded CTP Preview Program. 5 September 2012.
  8. Bowden, Zac. Microsoft plans major platform upgrades for “Windows 12” that will modernize the OS with AI, faster updates, and better security, Windows Central. 28 March 2023.
  9. Jeff. A Look Back on 20 Years of The Skins Factory: Part 1, The Skins Factory. 23 February 2021.
  10. https://twitter.com/zacbowden/status/1752328042599330121
  11. Cutler, David; Plummer, David. The Mind Behind Windows: David Cutler, Dave's Garage. 21 October 2023.
  12. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  13. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  14. 14.0 14.1 Harris, Jensen. This Is The Missing Windows Startup Sound. 19 August 2022.
  15. Bowden, Zac. Microsoft plans major platform upgrades for “Windows 12” that will modernize the OS with AI, faster updates, and better security, Windows Central. 28 March 2023.
  16. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  17. Thurrott, Paul. 64-bit Windows 2000 on track for mid-2000, Windows IT Pro. 27 July 1999.
  18. Windows 2000 to Launch at Comdex, 64-Bit Janus in the Wings, Findarticles.com. 26 August 1999.
  19. Gilbert, Ben. Microsoft accidentally sent an Xbox One to a random guy months before it was announced, Business Insider. 14 September 2016.
  20. Warren, Tom. Microsoft cancels Surface Hub 2X launch, promises ‘major’ software update instead, The Verge. 3 February 2020.
  21. De Herrera, Chris. Windows CE / Windows Mobile Versions, Pocket PC FAQ. 15 November 2009.
  22. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  23. Microsoft’s HoloLens 2 To Launch With A New Windows 10, Report Says
  24. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  25. Chen, Raymond. By Grabthar's Hammer, it's a Galaxy Quest documentary, The Old New Thing. 17 October 2019.
  26. http://iowa.gotthefacts.org/011607/0000/PX00194.pdf#page=52
  27. Smrček, Jakub. OS Windows Mobile/Phone: strmá cesta historií (in Czech), Cnews.cz. 31 March 2011.
  28. 28.0 28.1 28.2 Chen, Raymond. Letting the boss think your project is classier than it really is, The Old New Thing. 6 May 2014.
  29. Porter, Mike (9 August 1998); Iowa District Court for Polk County. Plaintiff's Exhibit #6462, Comes v. Microsoft.
  30. Chen, Raymond. What was the codename for 64-bit Windows?, The Old New Thing. 5 December 2023.
  31. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  32. Sinofsky, Steven. PM at Microsoft, Steven Sinofsky's Microsoft TechTalk. 16 December 2005.
  33. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.
  34. https://www.cnet.com/news/microsoft-looks-beyond-vista-sees-vienna/
  35. Update for Windows (KB939853); MICROSOFT WINDOWS SERVER VIRTUALIZATION TECHNOLOGY CODE-NAME "VIRIDIAN"
  36. Thurrott, Paul. SuperSite Flashback: NT's First Decade, Paul Thurrott's SuperSite for Windows. 8 August 2013.
  37. Smith, Chris. Some Microsoft codenames, Chris Smith's completely unique view. 30 April 2006.