If you have multiple operating systems installed on your computer, you cannot backup the metabase.bin file from the non-current operating system.
If you have Windows 2000 Server booted from C:\Winnt and Windows XP is installed in D:\Windows, you cannot backup D:\Windows\System32\Inetsrv\metabase.bin.
Ntbackup 'thinks' that D:\Windows\System32\Inetsrv\metabase.bin is part of the System State in the Windows 2000 Server install because it fails to check the drive letter and path.
To workaround this feature, use a batch file to perform the backup. In the batch file, prior to executing Ntbackup.exe, rename D:\Winnt\System32\Inetsrv\Metabase.bin Metabase.old. After the Ntbackup.exe statement, rename D:\Winnt\System32\Inetsrv\Metabase.old Metabase.bin.