Windows Longhorn build 4088

6.0.4088.Lab02_N.040706-1655
	Build of Windows Longhorn
OS family
Architecture	x86
Compiled	2004-07-06
Timebomb	2005-01-02 (+180 days)
Works in
About
SKUs
	Professional; Preinstallation Environment
Key
	TCP8W-T8PQJ-WWRRH-QH76C-99FBW

Windows Longhorn build 4088 is a Milestone 7 build of Windows Longhorn. Previously only the Preinstallation Environment of this build was available until 13 January 2015 when the full version of this build was uploaded to the BetaArchive's FTP server.^[1]

Changes and fixes[edit | edit source]

This build no longer shows the boot screen upon initializing Preinstallation Environment and Setup. The boot screen when starting setup and WinPE was reused in Windows Vista build 5048.
A new version of DWM is included, rewritten in .NET managed code. It can be enabled using the instructions found on the Windows Aero page.
WordPad can now be opened again after being broken from builds 4081 to 4087.
The shortcuts in the quick launch are now present again on the sidebar and taskbar.
The CD/DVD/USB icon image now appears on the AutoPlay dialog.
Compatibility options have been readded after being absent in previous componentized builds since build 4081.

Bugs and quirks[edit | edit source]

Installation[edit | edit source]

As typical of builds in this build range, it tends to take a long time to install and can be unstable.
Various commands in WinPE's command prompt such as formatting a drive will not work due to VSSAPI.DLL being missing.
Redirections like 2>nul do not work correctly.
When booting to the desktop for the first time, spoolsv.exe will max out 1 CPU core.
When booting to the desktop for the first time, Personalized Settings may hang on Themes Setup. To fix the issue, open up Task Manager by pressing Ctrl+⇧ Shift+Esc, then restart the system. This will reboot the machine to the desktop. Alternatively, you can fix this by terminating regsrv32.exe (although this causes the system to enable the Windows Classic theme).
During the second stage of Setup, Task Scheduler throws out an error. However, the installation continues normally.

Upgrade[edit | edit source]

Attempting to upgrade from other builds is not possible as one of two outcomes may occur:

A bugcheck with error code 0x0000007E after the second reboot. This is commonly observed when trying to upgrade from non-componentized builds, such as build 4074 (via a registry tweak that reports it as a componentized build).
An error during the file copy phase.

WinPE[edit | edit source]

The mouse driver in this build's WinPE does not function on specific hardware configurations or hypervisors, and may require a keyboard to navigate through the installation procedure. This issue appears to be largely related to using a PS/2 mouse, as most ordinary USB mice appear to function properly in setup.
Attempting to use the copy command in WinPE to copy files over from the the CD drive to a formatted Hard Drive will cause a FAT_FILE_SYSTEM BSOD.
Various commands in WinPE's command prompt such as formatting a drive will not work due to VSSAPI.DLL being missing.

Timebomb[edit | edit source]

Unlike other Longhorn builds, it contains a broken timebomb and can be installed on the current date. However, before installation, machine time will still be checked and verified.

Outlook Express[edit | edit source]

Outlook Express does not start due to registry errors and certain dependencies on WinFS.

Explorer[edit | edit source]

CD, DVD, and floppy drives appear and behave like local disks.
Help and Support crashes Explorer.
Explorer will crash after adding the display tile in sidebar and won't launch again. A workaround is to create a new account via cmd.
On first boot after Setup, some texts in Explorer and taskbar will appear as empty square symbols. This bug only happens on first boot and will go away after a restart.
When the Aero taskbar and sidebar are enabled, the Taskbar erroneously uses the Sidebar background.
The sidebar notifications and system tray doesn’t render correctly.

Control Panel[edit | edit source]

Hardware and Devices folder does not open.
By default, the Phone and Modem Options Control Panel applet name is empty.
When launching Computer Management, there is a chance that script errors will be displayed relating to missing registry entries.

Hardware / Drivers[edit | edit source]

This build will randomly access the floppy drive (if present).
On some boots, Windows may not detect the CD/DVD drive.
On some computers, you will need to enable VGA Mode after installing video drivers or the system will result in a blue screen of death with the error code 0x000000B4.

TCP/IP bug[edit | edit source]

The TCP/IP stack tends to malfunction, as it will result in a BSOD with the error code 0x000000D1.

Windows Product Activation[edit | edit source]

Windows Product Activation is missing.

Safe mode[edit | edit source]

The Safe mode is completely broken and results in a bugcheck with code 0x0000007B. This is because the Safeboot key, located in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control is largely incomplete and missing a lot of entries. Restoring the key from an earlier build with working safe mode allows this build to boot properly, but the video driver will not initialize properly. As a result, the operating system will freeze as it transitions into graphical mode, so Safe Mode is currently known to not work on these pre-reset Longhorn componentized builds.

Other bugs[edit | edit source]

The Task Manager in this build has a chance of hanging when launching a new task if Windows Explorer is not running.
When shutting down, restarting or logging off, there is a chance that the system will refuse to log off and get stuck on the Logging off... screen. Should this happen, shut down the system by pressing the power button once. This will trigger the Emergency Shutdown function and shut off the system.
The color depth is set to 16-bit by default, rather than 32-bit. This also appears in build 4093.
The Quick Launch and Classic Tray tiles exhibit an unique bug in this build, as each icon is displayed in a different row.