Quote (DCSS @ Jan 15 2018 05:32pm)
delete EVERYTHING you want gone. At this point, the illegal porn files are still on the drive and recoverable... so what you need to do is start writing to the drive a LOT. Just go from empty aside from the OS to being 100% full with garbage data, then delete it all again. Do it a bunch of times to be sure. Eventually the files will be gone/unrecoverable and you will be 'dataless' save for the OS.
Don't do this. The first part is correct, as in delete the stuff you want gone, but CCleaner has a function which can do a secure wipe of free space on your drive, so any potentially recoverable files that have been "deleted" are truly gone. Just run that instead of "writing garbage data".