Windows 8 build 7878

6.2.7878.winmain.101104-1752
	Build of Windows 8
OS family	Windows NT
Version number	6.2
Build number	7878
Architecture	x64
Build lab	winmain
Compiled on	2010-11-04
Expiration date
Timebomb	2011-07-01 (+239 days)
About dialog

Windows 8 build 7878 is a build of Windows 8, which was uploaded on 4 June 2021. Prior to being shared, seven screenshots of this build were included with the original upload of build 7746.

Editions and keys[edit | edit source]

Edition / SKU	Key
Home Basic	YGFVB-QTFXQ-3H233-PTWTJ-YRYRV
Home Premium	RHPQ2-RMFJH-74XYM-BH4JX-XM76F
Professional	HYF8J-CVRMY-CM74G-RPHKF-PW487
Ultimate	D4F6K-QK3RD-TMVMJ-BBMRX-3MBMV

New features and changes[edit | edit source]

The File History feature, originally known as History Vault, has been introduced in this build.
The modern setup client first introduced in build 7796 now includes a progress bar and has the ability to go online to check for updates.
The This copy of Windows is not genuine watermark no longer appears on the desktop.

Redpill[edit | edit source]

Immersive features[edit | edit source]

The Start screen tiles are now colored, and the Metro Horizon has been removed, although its resources are still present in twinui.dll.
Right-clicking on a tile now shows a menu with several options.
Pattern logon is available after setting EnablePatternLogonForInternalTesting in HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion to 1, however there's no option to use it on the login screen.
A new OOBE has been introduced.
A new AutoPlay dialog has been added, which is just the exact same as Windows 7 but larger.

Bugs and quirks[edit | edit source]

General[edit | edit source]

Shutdown or restart will cause a softlock when running this build in VMware Workstation 15 or newer. This can be worked around by using the host's Power menu.
Running this build in VirtualBox with the Hyper-V paravirtualization interface enabled will result in a bugcheck.
Certain visual elements in select MMC snap-ins (such as Services) may use the Wingdings font.
The name of the floppy disk drive driver remains in pseudo-language.

Setup[edit | edit source]

The last word of status messages shown when starting Setup and before the computer reboots into OOBE is cut off.
Attempting to select a network type will result in a driver unload bugcheck. To work around this issue, remove or disable any network adapters before booting into OOBE.

Shell[edit | edit source]

Enabling Redpill after upgrading from build 7875 will cause Windows Explorer to not respond when trying to load the Start screen and enter a crash loop. Using Redlock option 2 instead will enable Redpill features excluding the Start screen.
An unassigned file association error may occur if certain options in the Start tile drop-down menu are selected.
Changing personalization options may occasionally crash File Explorer. This is caused by InputSwitch.dll and can be fixed by replacing the file with a copy from build 7875.
The new language bar is mostly broken in this build and only works on rare occasions. It may occasionally spawn an empty, non-functional button between the notification area and the current date/time.

Themes[edit | edit source]

The title bar and watermark use the Arial font due to mistyping in the aero.msstyles and aerolite.msstyles files.
Only the top portion of the window frame is blurred when using the Windows Aero theme, leaving the side borders transparent.
The Windows Basic and the High Contrast themes do not render properly due to the enforcement of the DWM Aero theme.