Windows 8 build 7878

6.2.7878.winmain.101104-1752
	Build of Windows 8
OS family
Architecture	x64
Compiled	2010-11-04
Timebomb	2011-07-01 (+239 days)
Works in
About

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
Starter	7Q28W-FT9PC-CMMYT-WHMY2-89M6G

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 7814 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 if you set 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]

Installation[edit | edit source]

The messages shown when setup is starting, installing or upgrading Windows, restarting the computer or preparing the OOBE are cut off.
This build can't be installed or run on newer versions of VirtualBox, as a bugcheck will occur. This bug persists until build 8176.

Out-of-box experience[edit | edit source]

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.

General[edit | edit source]

If using VMware Workstation versions 15.x or above, attempting to restart or shutdown in this build will cause a softlock. To fix this, use the Power menu from the VM section.
Certain visual elements in select MMC snap-ins (such as Services) may use the Wingdings font.
An unassigned file association error may occur if certain options in the Start tile drop-down menu are selected.

Arial[edit | edit source]

This build uses the Arial font for the title bar and watermark because of a typo in the aero.msstyles and aerolite.msstyles files.

Aero[edit | edit source]

This build appears to have a slightly broken Windows Aero theme, with only the top portion of the window frame using the blur effect, leaving the side borders transparent.

Personalization[edit | edit source]

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.

Language Bar[edit | edit source]

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.

Redpill[edit | edit source]

Enabling Redpill after upgrading from build 7875 will cause Windows Explorer to not respond when trying to load the Start menu and enter a crash loop. Using Redlock option 2 instead will enable Redpill features excluding the Start menu.