Windows Vista build 6001.16637

Windows Vista build 6001.16637 is an unconfirmed Service Pack 1 build of Windows Vista, which was supposedly uploaded to the Chinese website BetaWorld on 26 July 2022.

According to BetaWorld Wiki, the Preinstallation Environment of the build was found in HP's "FREd Installer" installation package, which is suspected to be used to test PXE booting.