ianpit said:
The short answer to "Is Eraser really safe?" is "no". You cannot guarantee that it will erase all data. Using Piriform Recuva (a free program) I can usually recover at least a few files which have supposedly erased by Eraser, and this applies to the latest version (6.08) too. I've never had the time or patience to use the full Gutman method, but even setting Eraser to use 3 wipes can still leave recoverable data on the hard drive. I have experimented with other data cleansers (e.g. East-Tec Eraser) and they also leave recoverable data. Does anyone know how to really erase ALL data? Thanks - Ian
With due respect, this is both misleading and wrong. I need to explain why.
Firstly, a disclaimer. I post a lot on this forum, but I am an Eraser user rather than an Eraser promoter. If I find a better tool, I shall use it in preference to Eraser. So this post is about facts, and not about preferences or advocacy.
Every test I have run, using file recovery programs (typically Recuva, but I use others as well) and disk sector editors, clearly indicates that Eraser, assuming that it works which it now mostly does, erases exactly what you tell it to erase. Erase a file? It's gone. Erase free space? It's full of random data. In this sense (which is the only meaningful criterion you can apply), Eraser is safe. What is not safe is the disk system, particularly NTFS, which has been designed to protect data at all costs as though that is the only security issue that matters. There is no point in blaming Eraser for not erasing data during a free space wipe if that data does not actually reside in space marked as free.
That Is why Joel and I in particular have repeated probably dozens of times on this form that users need to be aware of the workings of the page file, of shadow copies (probably the most significant source of recoverable sensitive data), and of the logging activities of applications. I report the results of my most recent investigations in my post dated 19 June in
this topic, so I won't repeat all that here. The key point is that Recuva is finding data you didn't know was there in parts of the file system which are not free space, and are typically not in files that the user would delete as a matter of routine.
The post I referred to gives some hints on how to deal with at least the most obvious problems. If there is one key piece of advice, it is that the more you can separate the system (including applications) from data, the better chance you stand of fully removing sensitive data when you need to. Recuva routinely finds nothing recoverable on my data drive. That is never going to happen on a system drive.
So it's all about what might be called computer hygiene. No one application is going to give you that; you will need to use a number of tools (Eraser, CCleaner, system settings etc.) in a systematic way.Within such a system, Eraser is, in my experience, a useful and effective tool. Which is why it is both wrong and misleading to describe it as 'not safe'.
David
