Windows Longhorn build 4086 (lab03 dev)

Windows Longhorn build 4086 (lab03_dev) is a Milestone 8 build of Windows Longhorn. On 23 January 2020, this build was listed on a thread by UX.Unleaked blog founder Grabberslasher to be released to the BetaArchive FTP, and was later released in the tenth set of their 33 Longhorn/Vista builds on 2 February 2020 with its other compiles.https://www.betaarchive.com/forum/viewtopic.php?t=40726
==Changes==
*The setup text during the setup and hardware portions has been changed in this build, which is seen in Windows Longhorn build 4087.
==Bugs and quirks==
=== Installation ===
* Due to the later componentized builds, it tends to take a long time to install and can be unstable.
* Various commands in WinPE's command prompt such as formatting a drive will not work due to VSSAPI.DLL being missing.
*After the second stage of setup (hardware detection phase), the system will not restart automatically and get stuck on a blank screen with the desktop watermark. Simply reboot the machine to finish the setup.
====Upgrade====
Attempting to upgrade from other builds is not possible as one of two outcomes may occur: 
#A bugcheck with error code 0x7E after the second reboot. This is commonly observed when trying to upgrade from non-componentized builds, such as 4074 (via a registry tweak that reports it as a componentized build).
#An error during the file copy phase.
=== Timebomb ===
Unlike other Longhorn builds, it contains a broken timebomb and can be installed on the current date. However, before installation, machine time will still be checked and verified.
=== WinPE ===
* The mouse driver in this build's WinPE does not function on specific hardware configurations or hypervisors, and may require a keyboard to navigate through the installation procedure. This issue appears to be largely related to using a PS/2 mouse, as most ordinary USB mice appear to function properly in setup.
===WordPad===
WordPad does not start, as it will display with Failed to create empty document instead.
===Outlook Express===
Outlook Express does not start due to registry errors and certain dependencies on WinFS.
===Themes===
The Windows Classic style cannot be applied as there are no color schemes defined in the registry. Apply the following registry key to fix this problem:
===Explorer===
*Windows Explorer is more prone to crashing than in previous builds, especially when shutting down Windows.
*CD and DVD drives behave like local disks.
**As a result of this, the system continuously throws out notifications about low disk space.
*Help and Support crashes Explorer.
*Explorer will crash after adding the display tile in sidebar and won't launch again. A workaround is to create a new account via cmd.
=== Control Panel===
*Hardware and Devices folder does not open.
* By default, the Phone and Modem Options Control Panel applet name is empty.
*Computer Management displays script errors due to missing registry entries.
===Graphics===
On some computers, the system will bugcheck with code 0x000000B4 after installing the video driver. To fix this, enable VGA mode in the startup options.
===Windows Product Activation===
Windows Product Activation is missing.
===Safe mode===
The Safe mode is completely broken and results in a bugcheck with code 0x0000007B. This is because the Safeboot key, located in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control is largely incomplete and missing a lot of entries. Restoring the key from an earlier build with working safe mode allows this build to boot properly, but the video driver will not initialize properly. As a result, the operating system will freeze as it transitions into graphical mode, so Safe Mode is currently not known to work on these pre-reset Longhorn componentized builds.
==Gallery==
File:Longhorn40424093Boot.png|Boot screen
File:4086 Lab03dev setup.png|Setup
File:4086 Jade theme.png|Jade theme
File:4086 Luna theme.png|Blue Luna theme
File:4093 BSOD.png|System crash (usually appears after attempting to load Safe Mode)
File:SafeLonghorn.PNG|Safe to shutdown screen
==References==
Category:Windows Longhorn builds