Windows Longhorn build 3663

Windows Longhorn build 3663 is a confirmed but unleaked build of Windows Longhorn. It is the earliest known build for which screenshots exist.

Visual changes in the build include replacement of the colored Windows flag on the start button with a single white color variant. It also seems to have the login screen from build 3683 and disk space indicators in Explorer. Otherwise, this build is not much different from Windows XP or Windows Server 2003.

A rumor exists that the build was leaked in the far past, but due to the low interest, the download links were permanently removed. There is no evidence to support this rumor, however, and it can be safely assumed that there was never any leak beyond a few screenshots.