Windows Longhorn build 4088

Windows Longhorn build 4088 is a Milestone 7 build of the Microsoft Windows Longhorn operating system. Previously, only the Preinstallation Environment for this build had leaked. On 13 January 2015, BetaArchive user Daniel uploaded the full version of this build to the aforementioned site's FTP server.

Being near one of the final Longhorn builds, this build tends to take a long time to install and can be unstable. WordPad can now open again in this build. The Sounds control panel applet is found again and Scheduled Tasks folder is fixed in Control Panel. And some core features are also reverted back in this build.

Bugs and quirks

 * Partition and format a drive from a previous or later build prior to starting installation.
 * Safe mode is broken and displays a BSOD.
 * CD and DVD drives behave like local drives.
 * When enabling the slideshow sidebar tile,  restarts in a loop. Only fix is to remove the slideshow tile from the registry.
 * Help and Support causes an  restart.
 * Computer Management displays script errors.
 * The Windows Classic theme will not function due to a broken  file.
 * Outlook Express does not start.
 * 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.

Installation
The  part for setup tends to hang while trying to launch, you can try to open Task Manager on the second Command Prompt window by running   and then terminating   to get the hardware setup to load.