Windows 9 
(codenamed "Sunflower") was an operating system developed by Microsoft as part of the Windows NT family. Officially released on January 27, 2014, it served as the successor to Windows 8.1 and targeted both home and business users. Windows 9 aimed to address criticisms of its predecessor by reintroducing a more traditional Start Menu and focusing on improved usability, particularly for desktop users. While it maintained compatibility with existing Windows 8 applications, it also introduced significant under-the-hood changes to improve performance and security.
Development of Windows 9 began shortly after the release of Windows 8 in 2012. Microsoft aimed to address user concerns regarding the radical changes introduced in Windows 8, particularly the removal of the traditional Start Menu and the emphasis on touch-based interfaces. Early builds focused on refining the user interface, improving performance on lower-end hardware, and enhancing security features. A key goal was to create a more cohesive experience across different device types, including desktops, laptops, and tablets, without sacrificing usability for any particular form factor.
The development team, led by Adrian Malaka (born 1989), solicited feedback from Microsoft employees throughout the development cycle, incorporating many suggestions into the final product. The "Sunflower" codename alluded to Microsoft's desire to bridge the gap between the legacy Windows experience and the newer, more modern interface introduced in Windows 8. Public beta testing began in April 2014, allowing a wider audience to preview the evolving features and provide valuable feedback. This open development process proved instrumental in shaping the final release, ensuring that Windows 9 addressed the core pain points experienced by users of previous versions. Microsoft also collaborated with hardware manufacturers to optimize drivers and ensure compatibility with a wide range of devices. Significant effort was put into improving power management, resulting in increased battery life for laptops and tablets.
The official announcement of Windows 9, then presented as Windows 2015, took place at a //build/ conference. Microsoft highlighted the return of the Start Menu, improved search functionality, and a streamlined user interface. The company also emphasized the security enhancements, including a new version of Windows Defender and improved support for biometric authentication.
Extended support, which included security updates and critical bug fixes, continued until June 22, 2024. After this date, Windows 9 no longer received any updates or security patches, making it vulnerable to security threats. Microsoft strongly recommended that users upgrade to a more recent version of Windows, such as Windows 11[1], to ensure their systems remained secure and up-to-date. Long-time servicing, though, made it's debut for USD 129.99 a year, and will be active until 2034. Windows 9 played an important role in the evolution of the Windows operating system. It represented a course correction after the controversial changes introduced in Windows 8 and helped to restore confidence in the Windows platform. Many of the features introduced in Windows 9, such as the improved Start Menu and virtual desktops, were further refined and incorporated into subsequent versions of Windows.
Trivia[]
- This system can display a special Unicode character called the "Microsoft 9". The Microsoft 9 is used as the system's kernel version as well as the version name, so applications don't confuse the operating system with Windows 9x. You can type the Microsoft 9 into Visual Studio by pressing Ctrl+Win+9.
- Education and Ultimate editions haven't appeared until late in development.
- Has been mentioned as Windows 8.2[2].
Editions[]
- Windows 9 Thin PC Edition
- Formerly mentioned as "Home" edition in some internal documents, the name was changed a few days before release.
- Additionally, has a second name - "Embedded" edition, which can run at the lowest requirements since Windows Vista.
- Both Embedded and Home editions do have AI support.
- "Server" edition has been cancelled in favor of Embedded.
- Widgets are disabled here.
- Windows 9 Enterprise Edition
- Formerly mentioned as "Professional" edition, has met the same fate as "Home".
- Some of the "Server"'s functions were migrated to "Enterprise" in early 2015.
- Has a personal information manager added.
- Windows 9 Education
- Has additional external management functions like parental controls.
- AI is disabled by default in this version, but it's files remain.
- There is a website whitelist embedded (unlike /etc/hosts/).
- Only selected apps are allowed, like Pinta, Chromium, LibreOffice, etc.
- Windows 9 Ultimate
- As all editions, doesn't have media players bundled to comply with an antitrust ruling[3].
- Has a personal information manager added with a bit less functions.
| Feature/Edition | Thin PC Edition | Enterprise Edition | Education Edition | Ultimate Edition |
|---|---|---|---|---|
| Maximum physical memory
(RAM) |
16 GB DDR2
32 GB DDR3 |
256 GB DDR4 | 256 GB DDR5
32 GB LPDDR5 |
256 GB DDR5 |
| Maximum physical processors | 64 | 64 | 64 | 64 |
| Subsystem for Android applications | No | 11 - 13 | 4.3.3 - 9[4] | 11 - 13 |
| Parental controls | No | No | Yes | Yes |
| Homegroup | Join | Create and join | Join | Create and join |
| Encryption | Not present | Present | Present (BIOS/UEFI) | Present |
| Sandbox | Disabled by default | Yes | No | Yes |
| Presentation mode | Yes | Yes | Yes | No |
| App locker | No | Yes | Yes | No |
| Windows installer | Yes[5] | Yes | Yes[6] | Yes |
Differences with previous Windows systems[]
Windows Longhorn[]
- Pinball has been returned for the first time since Build 5048[7].
- World Record List has been added. As of 05/30/2025, the current WR Holder is UfahTrainer8 with 126,612,500 points.
Windows Vista[]
- Briefcases have been reworked.
- ZIP passwords have been re-done.
- Metadata editing has been re-implemented.
- Alternate Data Streams are now viewable.
- In late 2025, a KB57494645 update has been released to implement 16-bit app support.
- Microsoft Agent is now supported again.
Windows 7[]
- Wallpaper packs are back.
- Windows Calendar has been re-added.
Build list[]
Build 9698[]
It is the earliest available build of Windows 9. It was distributed to Microsoft partners and employees, which refer to the build as "Windows Preliminary Assessment System". It includes few of the new Windows features, and was intended mainly for the reasons of checking compatability of hardware and software with the upcoming system.
Build 9698 was based on the rewritten Minwin. The executable reported itself as PYMWCC. Previously, it was speculated, that the only known variant to exist, "6.4.9698.x86_64chk.private/winsat.A" can only run on a machine with atleast 1 GB of RAM and 32 GB of disk space, but in the leaked on January 31, 2026 documents, new compliance specifications were found, and are as follows:
| Detail | Embedded | Thin PC | Enterprise Edition |
|---|---|---|---|
| RAM | 512 MB DDR2 | 1024 MB DDR3 | 1536 MB DDR3 |
| Processor | 1.0 GHz, 1 core | 1.8 GHz, 2 core
Intel Core 2 Duo E4300 |
2.0 GHz, 2 core
Intel Core 2 Duo E8400 |
| Videocard | 64 MB
640x480 resolution |
512 MB
ATI Radeon HD 4830 |
1 GB
ATI Radeon HD 5830 |
| Disk space | 4 GB
SD Card |
20 GB
HDD |
40 GB
SSD |
Compilation date is unknown, and is speculated to be between October 2013 and April 2014. Later, it was replaced by the Windows 8.x-compatible installer check.
Build 9704[]
Developer Preview build, showcased and distributed to participants of //build/ 2014 conference, which was held from April 2 to April 4, 2014. Build tag was "6.4.9704.x64.winmain.140404-0404". The build was leaked to the Internet in July 2025 by the user "BlueScreenOfHappiness", with other materials from the conference confirming it's existence. Due to it's earliness, it served as a critical checkpoint in Microsoft's iterative development process, focusing on gathering feedback and identifying bugs before broader public releases. Had a timebomb set to July 5, 2015(+457 days). This build offered an initial glimpse into user interface changes, core system enhancements, and new applications.
Build 9712[]
Windows "Cosmos", specifically 6.4.9712.fbl_partner_eeap.140412-1412, represents a significant, albeit accidental, disclosure of an internal Microsoft Windows development build. The "Cosmos" designation, presumed to be an internal codename, was never officially recognized in any public release. This particular build, compiled on April 12, 2014, at 14:12 UTC, was inadvertently pushed to a subset of Windows Update users, resulting in a brief period of availability before Microsoft issued a rollback. The leak provided a rare, albeit unstable, glimpse into the development trajectory of Windows Telluride.
The accidental release of Build 6.4.9712 occurred on or around April 15, 2014, affecting a limited number of users who had opted into receiving updates from Microsoft’s "prerelease" channels. According to a post-incident report compiled by the Windows Update team, the error stemmed from a misconfiguration in the deployment scripts used to target specific test groups. "A logical error in the targeting parameters caused Build 9712 to be offered to a wider audience than intended," the report stated. This resulted in the build being incorrectly flagged as compatible with systems outside the intended test ring, leading to its inadvertent distribution. The incident was detected within hours, and a rollback was initiated to prevent further installations. Microsoft estimated that fewer than 0.1% of Windows users received the update before the rollout was halted.
Updates, noticed in "Cosmos", were:
- New Windows kernel: Windows reported Continuum Core 7.5/NT 6.4.
- Power consumption optimization: Some households reported better performance and lower costs of maintaining a computer after using Cosmos.
- 1st patch: On April 17, 2014, an upgrade appeared for the users, 6.4.9713.winmain.140714-2400, which locked access to Cosmos on and after May 15, 2014.
- The following notification had been enabled in the update through Verbose Login:
- This build of Windows will expire soon Your license to use this evaluation version of Windows will expire soon. When it will expire, your PC will be automatically reverted to Windows 8 or 8.1.
- The following notification had been enabled in the update through Verbose Login:
- Artificial Intelligence: In this build, something, that would turn into Cortana would appear. It didn't talk, but it did provide necessary system functional.
- In one of now-removed July 2017 blog, one architect shared, that the AI model used was based on experimental Seq2Seq technique.
- It had recieved local updates even past May 2014, last one being in late 2024, bringing parameter number up from the initial 6 million to 550 million.
ISO remains unleaked to this day.
Build 9725[]
Build 6.4.9725.private/athens.140525-0459 was a significant Milestone 1 build of what would eventually become Windows 9. This build which was compiled one early May morning offers a crucial snapshot into the developmental stages of the operating system as Microsoft transitioned from the Windows 8.x era towards a new, unified platform approach.
Was a private build initiated, most likely, by Microsoft Greece.
There were under-the-hood upgrades:
- Start menu: The MetroUI start is now out with 2 options:
- Full-Screen Start menu, reimplemented
- Small taskbar Metro-styled Start menu with widgets
- Hot Corners: now an optional feature.
- Charms bar still is a crucial part of a system.
- Touch no longer a priority: now, devices without touchscreen support can enjoy all the same functions as others.
- Cosmos functions were implemented, mostly with power efficiency.
- Artificial Intelligence has been doubled in size to near 14 million parameters.
- Historical Themes were added:
- Texas: Slate, Plex, Aero
Build 9726[]
Sometime between 24th and 31st of May, 2014, build 9726 was compiled. The only things known about it are:
- Windows Search has been upgraded with AI.
- Windows Activation is present again with a renewed design.
- The following key has been revoked: CWMY2-V4YPB-TJ20K-XTMBG-V3R32[8].
- Some software from Windows Longhorn has made it's comeback.
- Themes were added: Silver, Zune, and Jade.
It was lost to history sometime during January 2015.
Build 9779[]
Was the RTM release in June 2014.
- 9779.16384.winmain.140622-0400 was the RTM build.
- 9779.16384.0145.fbl_winmain.170519-0300 was a patch for the RTM build, released due to Wannacry outbreak, patching CVE-2017-0145.
- 9779.16384.0145.fbl_winmain.170520-0000 was a patched build for the patch of the RTM build, patching Mirai botnet, released on May 20, 2017.
- 9779.16384.0145.fbl_winmain.170706-0000 was released on July 6, after servers hosting Petya and NotPetya malware were seized by Ukrainian government.
Startup
Shutdown
Gallery[]
TODO: REPLACE SEARCH, WINDOWS 9 DISK, BSOD.
- ↑ Formerly, 'Windows 10 or Windows 11'. This has been removed due to Windows 10 nearing EOL (1 year until EOL in 2024).
- ↑ A real-life trivia for Windows 10 1507, found from BetaWiki:https://archive.org/download/6.4.9807.0.fbl_partner_eeap.140803-0005_EEAPNotes/Windows_8.2.pdf
- ↑ Case T-201/04 brought on June 7th, 2004 by European Commission against Microsoft Corp., decided on September 17th, 2007. There's been precedent: Case COMP/C-3/37.792. In total, Microsoft has been fined 4,04 billion dollars.
- ↑ Powered by Android x86 / BlueStacks
- ↑ Only for Windows XP, Vista, 7, 8, 8.1. Usually superseded by Live CD.
- ↑ Since 2017, it is possible to install RED OS or Windows 9 Education from Windows 8.1 or later.
- ↑ Per BetaWiki: The game in both its 32- and 64-bit forms remained playable on later versions of Windows, and was last included in Windows Vista build 5048. (https://betawiki.net/wiki/Full_Tilt!_Pinball)
- ↑ Jeffrey Epstein's key for Windows 7 Home Premium Dept. of Justice of the United States of America (Trump II; AG Bondi; 2026-01-12)