FRIHOST FORUMS SEARCH FAQ TOS BLOGS COMPETITIONS
You are invited to Log in or Register a free Frihost Account!


How to completely delete a file?





likeabreeze
By "completely delete", I mean by no means can the file be recovered.
Right click>delete never work.
Formatting the disk don't work, either.
but, How?
I've been told that overlapping the file is the only way to do this, really?
cybersa
By overlapping we can do it.
See here for information:
http://technet.microsoft.com/en-us/magazine/dd334519.aspx
likeabreeze
cybersa wrote:
By overlapping we can do it.
See here for information:
http://technet.microsoft.com/en-us/magazine/dd334519.aspx

At the web page, I notice there is "TechNet Magazine > Home > Tips > Windows Vista > Delete Files Permanently with SDelete".
Is SDelete Tool only for Vista users?
Or, for all Windows OS?
by the way, is overlapping the only solution?
cybersa
likeabreeze wrote:
cybersa wrote:
By overlapping we can do it.
See here for information:
http://technet.microsoft.com/en-us/magazine/dd334519.aspx

At the web page, I notice there is "TechNet Magazine > Home > Tips > Windows Vista > Delete Files Permanently with SDelete".
Is SDelete Tool only for Vista users?
Or, for all Windows OS?
by the way, is overlapping the only solution?

I tested it on Windows 7.
It was worked well.

I think overwriting is the only solution.
william
That program still won't work completely. If you truly want your data destroyed, your only options are a powerful magnet or a shredder.

Effectively when you Shift+Delete, all Windows is doing is removing the index for the file so it can be written over later. These files can easily be recovered with a program like Restoration (I've used it restore 100s of gigabytes of accidentally deleted files). The program above overwrites the file so in theory any program shouldn't be able to recover the files. Similarly, you can zero a hard drive using a few simple commands that effectively overwrites the hard drive with 0s. However unless you do several passes of zeroing, as well as variations with 1s included, your data isn't completely wiped.

Here's why. Even if you constantly fill a hard drive with a series of full-0s and full-1s, magnetic ghosting is still present. With sophisticated hardware you can find some, if not all, of the data that was once present. In some cases you'll find that when you overwrite a hard drive with just 1s, data that was originally 0s would be more like .95 and data that was originally 1s would be more like 1.05. There's also a technique that involves offsetting the hard drive head, reading, offsetting again, and reading on and on to recover the data.

A normal person would rarely have access to equipment capable of this. That said, if you're really paranoid, know that the above program and even zeroing doesn't fully terminate the data. Heck, if you just use the above program, I bet another program could at least recover some of the old data, like the name of the file. If you don't want to get physical with the hard drive, I suggest several random writes consisting of full 0s, full 1s, and randoms. Not fool-proof, but the more writes the better. But there is a reason why companies with classified information always shred the drives.
cybersa
webyishu wrote:
ԸʽӲ...

Is it spam message or other than English?
Qantas94Heavy
cybersa wrote:
webyishu wrote:
ԸʽӲ...

Is it spam message or other than English?


I'm 100 percent sure that's spam. Anyway, back on the topic. I'm assuming that you have a traditional HDD for this.

In theory, the only real way that I can think of (note: this may still not work) would be to run different algorithms (including all 0s) of overwrites of the HDD, then (if possible) formatting it and placing random files on there until it reaches complete capacity, and then overwriting it again using a different algorithm. After many times of doing that, place very strong magnets on each of the platters individually, and then physically destroy it by melting the metal making it into some random shape and then repeating the cycle numerous times with multiple magnets, then after a few cycles grind it into tiny pieces and dispose of it somewhere secure and inconspicuous, but just before disposing of it run it through with the magnets one more time.
subhan1
I think win7 solution should work - for older versions you can try simple overlapping - or by formatting then filling up the entire disk - which will quite take your time - there will be so many easy methods available @ Google Smile
microkosm
For the average person who just wants to get rid of naughty stuff downloaded from the internet a program like Eraser is perfectly adequate. Actually, this program is adequate for 99% of people out there as it can overwrite files according to US Department of Defense specifications (I think that's around 30 overwrites with 1's and 0's)

Sure, if you want to completely render a hard drive useless take the magnet and/or hammer to it, but I don't you need to take such drastic measures. Next time try encryption so you don't have to worry about silly stuff like this.
slimviking
likeabreeze wrote:
By "completely delete", I mean by no means can the file be recovered.
Right click>delete never work.
Formatting the disk don't work, either.
but, How?
I've been told that overlapping the file is the only way to do this, really?


this tool is free and very effective

http://www.cylog.org/utilities/cybershredder.jsp
Jamestf347
Honestly, it may seem like it's going to be deleted forever, but in reality destroying the hard drive with an magnet or just in general is the only way. Formatting is a minor way, but when computer forensic specialists recover data, they physically take off the layers of the disc to recover data. But the eraser will work if you don't ever plan on anyone doing this to your hard drive ha. Razz
zaxacongrejo
If you want to erase for ever
Format and disck
Fill the disk space again with data till it stay full
Format again
Fill the disk space again with data till it stay full, format again
Fill the disk space again with data till it stay full

If you just want to delete a file that you cant kill the process use this
http://unlocker.softonic.com.br/
firstroad
what's wrong with shoft+del?

you can also open the file with a text editor and delete all the chinese stuff you will see there and then just delete it...
Qantas94Heavy
firstroad wrote:
what's wrong with shoft+del?

you can also open the file with a text editor and delete all the chinese stuff you will see there and then just delete it...


As said before, on Windows (at least) Shift+Del will only remove the listing in the "index" of files that the hard disk holds, and mark that space as being "available" for other

For your other method, if the file size is smaller, then that section once occupied would be simply be marked as being available/free, but if you deliberately wrote a lot of null characters into the file, you could in theory "delete" it (at least safe enough for most consumer recovery tools to not be able to retrieve the file). However, there is still "remnants" of the original file in terms of magnetism (see william's response above for more details about this), which (in theory at least) could be recovered enough to provide proof that you had that particular file/text on your computer.
codersfriend
CCleaner has a feature called drive wiper. This is for files that already have been deleted and you don't want them to be recovered on your hard drive. It encrypts the deleted files making them almost impossible to recover.
firstroad
Qantas94Heavy wrote:
firstroad wrote:
what's wrong with shoft+del?

you can also open the file with a text editor and delete all the chinese stuff you will see there and then just delete it...


As said before, on Windows (at least) Shift+Del will only remove the listing in the "index" of files that the hard disk holds, and mark that space as being "available" for other

For your other method, if the file size is smaller, then that section once occupied would be simply be marked as being available/free, but if you deliberately wrote a lot of null characters into the file, you could in theory "delete" it (at least safe enough for most consumer recovery tools to not be able to retrieve the file). However, there is still "remnants" of the original file in terms of magnetism (see william's response above for more details about this), which (in theory at least) could be recovered enough to provide proof that you had that particular file/text on your computer.


thanks for the information
theinfernox
Use "Eraser", it permanently removes a data by overwriting the original data many times with bytes in particular orders. This makes it almost impossible for modern computer forensics to recover data.
The current most recommended way of removing data is:
The Gutmann Method. 35 pattern rewrites.
DoD 5220.22-M. 7 rewrites passes. By the US DoD(Department of Defense).

More info can be found in the wikipedia: http://en.wikipedia.org/wiki/Data_remanence

Eraser Link: http://eraser.heidi.ie/


Regards, Very Happy
codegeek
I generally use a shredder application for this. How safe would that be? Are there any traces left?
Sabbadon
I know I'm perverted but I use this method to erase docs that must not be in an HDD:
1- CUT from the HDD and PASTE USB Pendrive.
2- use CCleaner program to wipe the free space on HDD
3- use DiskWipe program to format the pendrive
Arrogant
Try a Shredder Application like Tuneup shredder or something like that
They do the job..
Related topics
Xbox Softmod Tutorial
Best Recover/undelete Files Aplication
Windows XP the best?
Virus Problem
Ipod video
chmod by apache
Can't delete file?
File recovery question
GMail Drive
NTFS or Fat32??
File "doesn't exist"
Stranged thing ever happend on your pc
Delete An "undeletable" File
Macbook: safe deletion
Reply to topic    Frihost Forum Index -> Computers -> Computer Problems and Support

FRIHOST HOME | FAQ | TOS | ABOUT US | CONTACT US | SITE MAP
© 2005-2011 Frihost, forums powered by phpBB.