That’s to say, your Win7 files have rewritten part of your data and you can never recover this part data.
However, do not give up. You also can try a free data recovery tool
to recover the rest part. I trust this freeware can help you a lot since my friend has tried it ever. This result is perfect. You can download it: http://blog4mark.blogspot.com/2012/12/photo-recovery-after-delete.html