Windows Vista build 6001.18000

Windows Vista build 6001.18000 is the official RTM build of Windows Vista Service Pack 1. It was made available to MSDN subscribers on 15 February 2008 and released to the Microsoft Download Center and Windows Update a month later, on 18 March 2008.

Changes from Windows Vista RTM

 * A new background is used for Windows Setup and Windows RE, which resembles the login screen background.
 * Disk Defragmenter reintroduces the ability to specify which drives to defragment.
 * BitLocker Drive Encryption now supports multiple partitions.
 * Added support for the exFAT file system.
 * Windows Activation received changes in its overall behavior. all premium features (including Windows Aero) will remain functional and a dialog warning the user that the copy of Windows is not genuine will appear at periodic times, instead of booting into "reduced functionality mode" and an hourly system reboot.
 * DirectX has been updated to version 10.1.
 * UEFI firmware support has been added for 64-bit versions.
 * Windows Update now shows more detailed information when configuring an update during shutdowns and restarts.
 * The Search link on the right pane of the Start menu has been removed. Additionally, the Search option in contextual menus for Windows Explorer folders has also been removed.
 * The ability to purchase a digital license through Windows Anytime Upgrade has been removed. This is due to Microsoft ceasing all digital license distribution on 20 February 2008. To continue using the service, users would have to purchase physical copies.
 * Improved performance and stability.
 * Improved wireless support.

Bugs
The initial deployment of the service pack to MSDN subscribers caused a number of machines to continually reboot, rendering the machines unusable.