Thread: erasing history.

How do you erase history from your computer?

Do you mean other than dumping it in a tank of concentrated sulphuric acid?

sure. i think we can skip that method :wink:

Never mind, i figured it out.

One thing you have to remember is that deleting your (internet I guess?) history is not permanent at all.

Data on harddrives can be recovered after they've been deleted, even if they've been overwritten a couple times.

If you overwrite data in say around 8 passes, overwriting with random characters and zeros then there's a good chance they can't recover it, but in fact they potentially still can due to error tolerence in the position of the head over the platter of the harddrive.

The only sure way of getting rid of data is to pass a very strong magnetic field onto the harddrive, then put it into an incinerator or some-such.

The wonders of harddisk technology! There was a big /. debate about this a few months back; the US military now agree the only way to eradicate data is that previously mentioned really.

Thanks, but I dont have anything to hide, especially nothing that serious!![/i]

Originally Posted by pendragon526

Thanks, but I dont have anything to hide, especially nothing that serious!![/i]

Well, I just wanted to be thorough :-)

its all to do with how the computer saves the information

when you delte a file the computer is lazy, instead of irasing all the information, it just overwrites the intitial character from the title line that the computer uses to indentify a file. Thist ells the computer that the following area is an unallocated disk space and can be overwritten. With appropriate analytical sodtwear, forensic computer experts can search for files with broken labels, rebuild the label and open the file.

The only problem for forensic examiners is that once a dile is "deleted" the sapce on that disk becomes availble for the computer to overwrite it with a new file. It this has happened the information may be lost. But there are ways around that problem too. When a computer saves a larfe file, it often breaks it into smaller chunks and spreads them around the disk. It may be that the computer has overwritten one of more the small regions, but a forensic computer expert can calvage enough from the areas that haven't been distoryed to retrive the evidence they are after. A delted and overwritten file of an image of child porongraphy could be recontructed to a suffient extent to infriminate the computers owner.

Even if the date has been overwritten a number of times it's all computer systems, including electronic diaries, leave some kind of trail. As long ago as 1986 drug smuggler Paul Dye was ocnvicted in the UL on the basis of files apprently deleted but recovered from a Psion electronic diary. Forensic experts had to get a Psion corporation to build the appropreiate tools but it was possible to do.

source
the forensics handbook
the secrets of crime scene investigation
Pete Moore