In order to install the Windows XP Ntbackup program on your Windows Vista computer you will need to following files from a Windows XP computer:
These can be found in the C:\Windows\System32 folder of Windows XP.
You could also copy these help files, but you don't really need them:Ntbackup.chmNtbackup.hlp
These can be found in the C:\Windows\Help folder of Windows XP.
Copy all 3 (or 5) files to a folder in your Vista Program Files folder, for example use C:\Program Files'Ntbackup. Since you won't be pasting these files in the system path there is no need to worry about overwriting files.