Summary and Easter Brain Food
Warning, long post. Useful for folks passing by or killing time.
I've been dealing with highly confidential data for many years (banking and finance, personnel records, tax data), and delved deeply into several operating sytems and their security and privacy weaknesses. Eraser is a damned good tool. Use it, but there is a lot more. I don't delete any more, haven't for years. Just got into the habit of erasing. And Eraser does it.
There a lot of good sensible posts on this site, and there is a lot of combined experience (Duke, if he is the orginal of that nick, has been around for many years), but there are also some posts that are entirely ludicrous, laughable. There is a mix of the curious, the geeks (I would count myself as a minor guru), and, probably the most important, people who just want to be careful and would like to know what really works, and whether they really need wait hours for a 120Gbyte drive to be cleaned.
For the last category, try this for a quick summary with some of my own input. There is also a bit of "food for thought". Comments welcome:
1)It is possible and has happened that people have been busted and their computers confiscated "for investigatory purposes". Most often there is already a "reason" for this (your credit card number was found on a suspicious list, you "visited" a dodgy web site (no you didn't, you went to a linked page and your ip got on the log) etc etc but our good old law enforcement people are nothing if not thorough and patient. So covering your tracks on the internet should be a prime concern, not just erasing data. There are ways to do that which you can pick up as you go.
Its certainly no fun to be told you are in the clean and free to pick up your gear from some storage compound if it is 6 months or more down the line and you have had to scratch around for even the phone numbers of friends, acquaintences, and business contacts during that period. It also happens that said gear has been badly treated by underfunded, undereducated twerps who know less than a total newbie, and it don't work any more. Its worse if you have some nut in your office who has been using his work machine for dubious practices only to have your entire office network dismantled and carried off by a harassed looking law enforcement officer. Give that person a break please. They just want to get it done and go home. But your business or job may just have been hosed. How many businesses can survive for long with everthing gone? Backups? Gone as well. They are also potential evidence.
In other words paranoia is not necessarily a bad thing. If in doubt, Erase.
2)But get real. Maybe you do have a bit of copied software or some pirated cds, dvds. Maybe there are some pics on your drive that are legal/grey but you'd rather not have it known that you have them. Maybe you did shave your last few tax returns tight. Maybe you do have a bank account or two that you'd rather your spouse/lover/boss/creditors didn't know about.
Windows in particular hoses, but hoses like it was being paid for it, your drive with "evidence" in the form of temporary files, MRUs, index.dats etc. No app can get all of those, though there is one, and only one, hyped Windows app out on the net that gets most of them. But its darned hard to keep a machine clean. It takes a lot of time and effort. Try finding out more about encrypted drives instead of worrying about erasing. Then discover you really need to know about BOTH, and a lot more! Most regulars or experienced visiting a site like this will already know that. Newbies won't have a clue beyond some half-learnt basics, folklore, and mis- dis- information. Get out there and learn if you think you need to, or are just passing time soaking up new stuff that might be useful one day.
3.You're probably here for info on erasing, so here is the REAL world :
A single pass of pseudo random data is about as good as it gets on modern equipment (post say 1998). Beyond that is hyper paranoia (nothing wrong with that if its your choice, its a free world -- (huh!)). If you want to check that then make a small partition, wipe it with Guttman. Then sprinkle it, fill it, with any files handy, preferably text files so its easy to see if there is anything left after a wipe because you can see words and sentences. Wipe it again with a single randon pass. Then do a recovery with any of the recovery software around. I use Easy Recovery Pro, but there are many. It will find nothing. To convince yourself further try a disk snooper (try Directory Snoop, does FAT and NTFS) that reads sectors one by one and look for text (try it before and after the random wipe). It won't find anything either.
That is IT, that's about as good as average law enforcement and criminal techniques of recovery get....UNLESS you are on a very special set of hitlists which warrant a LOT of money (like 100s of thousands, or even Millions of US$) being spent getting information from your computer. If you are on a list like that, as someone has already hinted, then it is not only your computer that will be a problem. Your mobile phone, home phone, office phone, your dining table, your neighbours upstairs bedroom, your best friend, your trash can, your shoes etc etc etc... are all liabilities. BUY a helicopter and a few spare passports but _don't_ dream.
Only a highly educated, experienced, hardened intelligence officer/ criminal, with lots of resources, money, and friends will have a remote chance of having covered every possible avenue and getting away with something they want to hide if the people who are looking are also highly educated,experienced, hardened, and well funded.
Better save your money for a good lawyer. At least that way if you are innocent of a major crime then you will get a better chance of having that proven to a court's satisfaction.
But if you are just an ordinary person who wants to educate themself and find out just how bad it gets, and you want to know more, a good starting point is Dr Who's privacy FAQ. Its around, try Google.
Oh and dont forget cd-roms and dvds. Most people make backups some of the time. Ever made a backup and then cleaned your machine? Ever thought about the backup program saving all your temp files for future generations? And an uncleaned/uncompacted Windows registry holds a lot of data. As does and uncleaned/uncompacted Outlook pst file or an OE dbx file. And those URLs in your favourites....
If you do need to clean or think its a good idea, fine. Make the backup, do the job, then make another, clean backup and destroy the first one. Like I said, its a pain in the b*** ! A microwave oven does a good job, they don't need cooking, just a brief flash. Quite pretty.
How to recognise the crap like the "history on your drive ..." idiot some posts above? Well if they start talking about stuff that sounds like techno-babble that none of the regulars agree with or have heard of then its garbage. Pure and simple. You already know more than they do.
Have fun!
