Windows Vista build 5000 (vbl core.040803-2000)

Windows Vista build 5000 (vbl_core.040803-2000) is the earliest known post-reset build of Windows Vista, based on a work-in-progress version of the Windows Server 2003 Service Pack 1 codebase. 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 released in the third set of his 33 Longhorn/Vista builds on 26 January 2020, alongside build 4048, other compiles of this build, and build 5001.

Changes

 * The OOBE process was introduced back into this build, OOBE missing the Question Mark assistant on the first page.
 * The  and About Program banners in the Professional SKU now has the "XP" changed to "lh".
 * A "Longhorn Help Place" button has been added to the Help and Support Center. When invoked, HelpCtr will attempt to launch, which does not exist in this build but does exist in some Longhorn pre-reset M6 builds, such as 4033.
 * The background of the User Accounts Control Panel applet has been changed from blue to gray. Gray is used as the overall color in Windows Server 2003.
 * Support for the Multilingual User Interface (MUI) feature has been implemented; although it is not functional as the resources located in the MUI are duplicated in the actual file.
 * The rewritten Event Tracing for Windows architecture already appears to be implemented in this build to an extent.

OOBE
The animated "Question Mark" assistant in the Out-of-box experience (OOBE) does not appear until reaching the second page. This is maybe due to bugs in the Microsoft Agent technology itself.

Windows Media Player

 * The visualizations in Windows Media Player are broken, and other compiles of build 5000 and build 5001 also have this bug.
 * Alchemy visualization in Windows Media Player won't appear unless the user runs.