Windows Longhorn build 4048

Build of Windows Longhorn
OS familyWindows NT
Version number6.0
Build number4048
Build labidx02
Compiled on2003-09-25
Expiration date
Timebomb+180 days after original install date
Product key
About dialog
4048idx02 winver.png

Windows Longhorn build 4048 is a Milestone 7 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 server, and was released in the third set of his 33 Longhorn/Vista builds on 26 January 2020, alongside multiple compiles of build 5000 and build 5001.[1] The shared ISO image is incomplete, hence parts of install.wim as well as all files below it are missing. As of 2024, the complete ISO of this build has yet to be found.

This build was compiled in evaluation mode and can be installed on the current date. Attempting to log onto the desktop once the timebomb has been triggered will return the user to the login screen.

File Recovery[edit | edit source]

The first two indexes (WinPE) of install.wim survived and the third index (Longhorn) got partially cut off. The file table is missing due to it being at the very end of the image, however it is possible to reconstruct the file table based on 4051's. The metadata resource of the first two indexes are intact, hence information such as attributes and timestamps is available. The third index is missing a good portion of compressed data and all of its metadata resource, so recovered files do not contain any (valid) metadata. Community member lucasm published a patched install.wim with a reconstructed file table and metadata resource for the third index based on 4051's install.wim on 31 December 2021.

Installation[edit | edit source]

Currently, the only way of installing this build is by copying the recovered files from the third index of install.wim onto a partition with build 4042 (Lab06_n) pre-imaged. Second stage setup will continue with files from build 4048 and eventually complete the installation. However, the installation using this method will be single-use only. It is unable to log on anymore once the user reboot or log off, so it is recommended to make a backup, or if using a hypervisor, a snapshot before the second stage setup.

An I386 repack with files taken from build 4051 is also possible, however there'll be many driver prompts showing up during installation due to the catalog files being missing, but this installation can be used multiple times and the user can still log on after rebooting or logging off.

Changes[edit | edit source]

  • A new winver banner has been added, which was first seen in build 4044.
  • The watermark has been changed to read "Windows® Code Name "Longhorn"" instead of "Longhorn [SKU name]". This was also first seen in build 4044.

Bugs[edit | edit source]

General[edit | edit source]

As mentioned above, it is not recommended to log off or restart on this build. If triggered, the machine will be unable to log on anymore (unless the I386 installation method was used). Therefore, it is recommended to make a backup before the second stage of setup, or if using a hypervisor, a snapshot is recommended.

Setup[edit | edit source]

It is unknown whether this build includes the redesigned Setup as seen in build 4050 due to the setup media being corrupted from install.wim onwards, making files containing setup assets unrecoverable. However, the setup.exe file located on the disc root suggests that this build most likely contained the redesigned Setup.

Gallery[edit | edit source]

References[edit | edit source]