Windows 8 build 7850

Build of Windows 8
OS family
Architecturex86, x64
Timebomb2011-02-05 (+136 days)
Works in
Win8 Build7850 Winver.png
TCB.png TCBGallery.png BA.png

Windows 8 build 7850 is a build of Windows 8. This build was originally shared as an x86 Enterprise SKU version on 12 April 2011,[1] then on 17 January 2015, an x64 version was uploaded of this build along with more SKUs for both the x86 and x64 architectures and its server counterpart to BetaArchive.[2]

Being early in development, many areas still say "Windows 7" and the kernel is still 6.1 (much like the earlier builds 7700 and 7746). The default background image of this build is a bluish gradient with a green tint at the lower right and a message at the top telling users not to leak this build ("shhh... let's not leak our hard work").

Editions and keys[edit | edit source]

Edition / SKU Name Key
Starter 7Q28W-FT9PC-CMMYT-WHMY2-89M6G
Home Premium RHPQ2-RMFJH-74XYM-BH4JX-XM76F
Professional HYF8J-CVRMY-CM74G-RPHKF-PW487
Enterprise H7X92-3VPBB-Q799D-Y6JJ3-86WC6

Redpill[edit | edit source]

The 2 March 2020 build of Redlock unlocks various features in this build. It's the earliest leaked build to implement Redpill.

The Start screen in this build is rather primitive, having only one view featuring every installed application with a tile. It also includes a button to bring up an early search pane. A very early and non-functional snap UI is seen when you exit from the Start screen. A primitive Charms bar is also implemented and is accessible by pressing Win+C on your keyboard, but it is non-functional. New folder icons, along with a preview grid, are present in this build when Redpill is enabled.

For an unknown reason, in Checked/Debug compilations of this build, the Start screen has a yellow-orange background instead of the white background seen in free compiles.

Other features include:

  • Support for 32-bit UEFI boot
  • Support for booting from an exFAT partition
  • 4K Native logical sector boot
  • Hybrid boot
  • Explorer Ribbon UI (icons are all circles)
  • User tile (located at the right of the taskbar)
  • Centered title bar text
  • Explorer up button
  • Built-in PDF Reader (basic)
  • Modern Task Manager (partially broken)
  • Webcam Application (full screen)
  • Built-in virtual optical drive (double-click the ISO file to directly mount the image)
  • Auto colorization of themes
  • ApplicationExplorer shell location (Applications.{4234d49b-0245-4df3-b780-3893943456e1}) - tabs include "Tile state" and "Host environment". This is where the Start screen app list is stored, even up to 8.1.
  • Aero Lite (labeled "Windows Classic")
  • Early beta build of IE9
  • Built-in USB xHCI drivers
  • Built-in UASP drivers
  • Certificates and digital signatures that recognize the SHA256 algorithm
  • New Disk Cleanup (diskclean.exe)
  • System reset (sysreset.exe)
  • Portable Workspace Creator (pwcreator.exe)
  • Each user's desktop wallpaper will also be applied to the lock screen for that account.

Findings, fixes, enhancements[edit | edit source]

PDF Reader[edit | edit source]

There is a very early version of the Immersive Reader included, accessible by running C:\Windows\System32\glcnd.exe with any PDF file as an argument (or without any argument to open a blank page).

Modern Windows Task Manager[edit | edit source]

A preliminary version of the Modern Windows Task Manager is included as well. It is accessible by running C:\Windows\System32\TaskUI.exe.

Ribbon UI[edit | edit source]

A Ribbon version of Windows Explorer is included as well. However, most of the icons for it are placeholder circle icons.

Webcam Capture Application[edit | edit source]

An early version of the webcam capture application is included as well, accessible by running C:\Windows\System32\Webcam.exe.

Auto Colorization[edit | edit source]

Create a copy of a theme from C:\Windows\Resources\Themes, add AutoColorization=1 to the end of the [VisualStyles] section and apply.

Miscellaneous[edit | edit source]

The Getting Started application from Windows 7 has been removed.

Bugs and quirks[edit | edit source]

General[edit | edit source]

  • On some machines, it is not possible to install this build due to a 0x7F bugcheck.
  • Some graphics drivers may prevent the system from booting and will result in an ATTEMPTED_EXECUTE_OF_NOEXECUTE_MEMORY bugcheck.

Installation[edit | edit source]

  • On some machines, it is not possible to upgrade to this build due to an error when booting into the OOBE.
  • The messages shown when the setup is starting or restarting the computer are cut off.
  • The original 2011 leak of this build is bundled with the Windows 7 RTM pre-installation environment.
  • Setup may hang when restarting after the hardware portion. Resetting the machine will fix the problem.

Timebomb[edit | edit source]

Unlike other Windows 8 builds, it contains a broken timebomb and can be installed on the current date.

Windows Basic[edit | edit source]

The Windows Basic and the High Contrast themes are broken.

Explorer[edit | edit source]

  • Changing the date has a chance of crashing the Explorer shell.
  • Using Desktop Gadgets significantly slows the OS down.

Gallery[edit | edit source]

References[edit | edit source]