Windows Longhorn build 4086 (lab03 dev)

Windows Longhorn build 4086 (lab03_dev) is a Milestone 7 build of Windows Longhorn. On 2020-01-23, 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 his 33 Longhorn/Vista builds on 2020-02-02 with its other compiles.

Bugs and quirks

 * Partition and format a drive from a previous or later build prior to starting installation.
 * CD and DVD drives behave like local disks.
 * The Windows Classic theme will not function due to a broken  file.
 * Safe mode is broken and displays a BSOD.
 * WordPad and Outlook Express won't start due to bugs.
 * Opening Help and Support results in an  crash.
 * Hardware and Devices folder does not open.
 * Phone and Modem Options Control Panel applet name is empty.
 * On some computers and virtualizers, the WinPE doesn't support the mouse, so you must use the keyboard to navigate the WinPE.