click-click, on 25 November 2011 - 07:11 AM, said:
Is it necessary to format the target partition for a clean Win7 install with WinNTSetup?
No, it's not mandatory. install will overwrite files and abort if there would be a problem.
But yes there will be files remaining from old Windows installation.
With removing an old installation without formating, i see 2 problems:
1. NTFS security settings
- one would need to take ownership & grant access
or using a tool like
xdel
2. Junctions and Symlink (and this is the thing that scares me !

)
- junctions and symlinks in Win7 are created with full path.
think you have an offline win7 that has C: as normal drive letter and is now under your current running windows mounted as D:
It's junctions and symlink will still point to C:, but that could be the current running windows
Even Mircosofts own tools like robocopy don't handle symlinks right.
It might happen that deleting an offline windows switch the drive and start deleting files/folder one the current system drive !
This post has been edited by JFX: 27 November 2011 - 02:03 PM