Ccleaner - Secure Deletion (Overwritting)

Anwer · 15 Jan 2016

Hi! I want to always Permanently Delete (Shred) files and folders on my PC so that no one can recover those data. Now I heard for a program called Eraser which allows us to shred files/folders by clicking right click of mouse on the files/folders and then choosing Shredding (Permanently Delete).

So my question is: can I normally delete all files/folders which means that those files/folders are now in Recycle Bin. And then I just open Ccleaner and I set Secure Deletion to Very Complex Overwrite (35 passes) and I also check 3 boxes there (Wipe Alternate Data Streams, Wipe Cluster Tips and Wipe MFT Free Space) and I also check Local Disc (C) and Local Disk (D) boxes and then I just click Run Cleaner and now all the files from Recycle Bin will be Permanently Deleted (Shredded) and no one will be able to recover those files? If this is true, then I don't need Eraser to permanently delete (shred) files/folders. So I'd really like to know the answer from someone who knows this for sure. Thank you for your time and your answers! Best regards!

Archie123 · 15 Jan 2016

I would say CCleaner does a better job than Eraser anyway , you dont need both :)

lx07 · 15 Jan 2016

If you are indeed using Enterprise then just turn on bitlocker and encrypt the whole drive.

You haven't filled in you specs but if you use HDD there is never any point overwriting more than once with zero. It could (theoretically) be retrieved bit by bit with an electron microscope but no-one (not even the US government or your mum) will have the finance to do that.

Overwriting 35 times is a joke and a complete waste of time. See here

If you have a SSD there is no need to overwrite anything at all. See here

When you want to give your disk away just "forget" your bitlocker password and you are done.

There are people who believe all sort of things though - for example the NSA has backdoors in Seagate and WD HDD. If you fit in that category then you are a bit stuck. That would mean you can't trust anyone, can't use any computer hardware and have to memorize everything or store it on a bit of paper under a park bench.

Could make life a bit inconvenient IMO but then you'd hardly be asking about it here if it was really a concern for you I hope..

Anwer · 15 Jan 2016

I am using Windows 10 Enterprise x64 and I use HDD. Since I'm always on web in incognito mode I don't collect any history and that's why I was using 35 passes for a long time - my computer is cleaned in few minutes even when using 35 passes hehe :) I trust you that 1 pass is enough, but It's just cool to me to clean with 35 passes hahah

But you still didn't answer my question - which is: When I normally delete files/folders it means that those files/folders are now placed in Recycle Bin, right? So, if I don't empty Recycle Bin, but I run CCleaner instead, does that mean that all those files/folders in Recycle Bin are gonna be overwritten with 35 passes and no one will be able to recover those files?

And I actually don't know what it means that BitLocker encrypts my whole drive. I'm kinda scared to do that because I never tryed to encrypt my drives so I don't know what that means, how will that look like and what will happen with my PC when that encryption is turned ON hehe :)

lx07 · 15 Jan 2016

If you are concerned about privacy I'd start here Tor Project: Overview

Don't get hung up on local risks though (someone taking away and analyzing your local disk) - you give much more away using google, posting on a forum or owning a mobile phone.

I use bitlocker just in case I leave my laptop in a taxi or in the pub (yet again). If I found your laptop in a taxi then I could read all your documents and emails, see what websites you visit and so on if it wasn't encrypted. So could anyone else.

Anyway to answer your question, yes. CCleaner overwriting things 35 times would make it unreadable (so would once). If you don't empty the recycle bin then the files are not deleted and not overwritten at all (they are only flagged as deleted but otherwise are the same on disk). What you don't realise is that you probably have other copies of files that can also be retrieved.

So best thing to do (minimum) empty the recyle bin and then overwiite clean space. Better, turn on bitlocker (then if you lose your laptop I can't read anything).

Even better, be careful who you reveal yourself to. Hide and encrypt everything on the internet. Always pay cash, use disposable passports and cell phones and never sleep in the same place twice.. That could be a bit of a hassle though I guess