Windows Longhorn build 4002 (Lab06_N)

Build of Windows Longhorn
OS familyWindows NT
Version number6.0
Build number4002
Build labLab06_N
Compiled on2003-01-08
Expiration date
Timebomb2004-01-06 (+363 days)
Media Center Edition
Tablet PC Edition
Product key
About dialog
TCB.png TCBGallery.png

Windows Longhorn build 4002 (Lab06_N) is a Milestone 4 build of Windows Longhorn. This build makes use of the Desktop Compositing Engine seen in earlier Milestone 3 builds and is the last pre-reset build to support being installed to a user-defined folder instead of C:\Windows. Grabberslasher first gave the details of this build on their UX.Unleaked blog. On 23 January 2020, this build was listed on a BetaArchive thread by the aforementioned user to be released to its FTP server and was released on 31 January 2020, alongside build 4040 and build 5356.[1] WinUnleaked also had images of this build.

Unlike later Milestone 4 builds and even build 4001, this build uses the old i386-based setup routine instead of the newer WIM installation format.

This build is specific in that it was compiled as a private build, with binary files having the VS_FF_PRIVATEBUILD flag set in their version information and the builder user name being present in the build tag, although the user name suggests that the build was compiled by the official Lab06 user account.

New features and changes[edit | edit source]

  • The new taskbar has been updated slightly, included a new clock on the taskbar, and a slightly lighter shade.
  • The sidebar has also been updated slightly, including the newer shade and slightly modified tiles.
  • A new wallpaper has been added, thus making this build the first Milestone 4 build to use a new wallpaper (unlike build 4001, which weirdly still uses the old Milestone 3 Longhorn background).
  • MyTVApp has been removed.
  • The sidebar also has some hidden tiles.[2]
  • The start page has some text changes; instead of saying "Just click on one of the links below to get started" it now says "Hover over one of the tasks below to get started".[3]

Bugs and quirks[edit | edit source]

General[edit | edit source]

  • WcmRegister.exe will throw out user registration errors upon login.
  • If Windows Explorer is restarted while an application is still open, closing the app will still have its taskbar task shown.
  • Windows may not register all available display resolutions on certain graphics hardware and driver combinations.

Installation[edit | edit source]

  • This build can't be installed via a CD boot by default because it attempts to incorrectly load the coverage.dll file. As a result, the system will throw an Unknown Hard Error bugcheck after formatting the drive due to loading this file. setup.exe also attempts to load this file and quits due to it, but running winnt32.exe can allow setup to load. To fix this bug, the file coverage.dll must be copied to the i386\system32 directory in the disc image.
  • During GUI setup, there will be a copy error that it fails to copy WinFSSyn.sql, WinFSSyC.sql, and WinFSSyM.sql, the user can safely skip copying these files. The title of the dialog box that appears when the user skips copying these files is incorrectly labelled as "Windows XP 64-Bit Edition Setup", despite being an x86 build.

Desktop Compositing Engine[edit | edit source]

When Desktop Composition Engine is enabled, it renders the graphics on the hardware layer, while the software layer is rendered as black or leftover data, which means that attempting to use software capturing methods (such as Print Screen) will not produce the screen correctly. Most hypervisors only renders the software layer, usually resulting in a black screen upon starting DCE.

Control Panel[edit | edit source]

Display Properties identifies the Luna theme as the Plex theme, which is a different theme.

Gallery[edit | edit source]

WinUnleaked images[edit | edit source]

References[edit | edit source]