[stevenicr]

are you 100% on "only check files which have been shared between users though." ? - I do not recall seeing that in the info I read some time ago.

"typically use hashes of files" - I don't think this changes anything as far as msoft employees and others looking at pics of your kids or wife /gf / bf, etc; if you have taken the photos or he/she did and sent them to you right? This would only remove some of the internet shared/saved photos from the pile right?

Privately taken pics saved on the windows computer are / would still be sent to employed humans to look at, from what I understand.