Knoppix STD can not write to NTFS partitions, will destroy the partition if you manage to get it to try.

Some people think Knoppix can now safely write to NTFS. I'm not convinced and would not risk my data to test it. You are free to do believe whichever you wish.

If I were in your case (although I can't imagine how that could happen), I would use Knoppix to recover what files I wanted from the system in question, then do a full reinstall of Windows (assuming you still want Windows). That way Knoppix only reads the disk, does not write it, which is safe. See the Rescue FAQ for details.

While we know of Knoppix STD here, it is very old, apparently abandoned, and we really can't support it.