Question about Data recovery????

[jalal]

Hi
I am a virtual dr student, i use this forum for getting help, today i want to know about Data recovery? let me simplify my question!!!

When we formate Hard disk, for example OS got corrupted, files missing, lets say we failed to fix it and format is the ultimate solution, Now if we put xp CD and boot it, the dard blue screen appears etc, and finally it says what you want to do with yr drive, for example it shown C drive already got windows, and i choose delete partation, then i recreate it and then i hit formate as NTFS for the installation of windows xp.... but here my D, E F.G H drives remains there, lets say they have got my data i.e Movies, pics.. documents, softwares etc etc

Now going back to that format place, what if i delete all my partations along with C, I.E D,E,F,G,H etc.. now it will show me collective space of my entire Harddisk like 500GB lets say...

Now i make again drives etc etc and finally install my windows on C drive as i mentioned earlier..

Now after all install i see my C drive for windows while D,E,F,G,H as empty as i deleted partations and then formated them...

People say its possible to recover data, that is deleted but at the same time they say not over written? I am confuse at this statement??? If One partition was of 40GB lets say it was D drive, i deleted it and recreated the partation with the similar sizes as it was previous now if i write 5GB data on this D drive then will it recover what it previous had on it before i deleted and recreated the partition( but here size as similar as it previous was, if it was 40 GB then it remains 40 GB after i deleted partation and recreated it)
So what does this over written means here??? Does it mean that 5GB space or equivalent data is over written so its impossible to recover while the rest of 44 or 4GB is recoverable??????????

Kindly educate me where data recovery is possible and in which formate or delete its impossible as people first say if you do this its impossible to recover but on the next forum they say its possible using this and that???

I want to know what i asked with straight answer!!!

Thankx

Jalal

[jerryctx]

Deleting a file does not remove the data. It only marks the file as deleted in the disk's "table of contents" (the FAT or MFT (NTFS)).

The data remains and can be recovered until the space is needed for a new file which overwrites the old file. Depending on where the file is located on the disk and how often you create and delete files, old data can remain indefinitely.

Formatting also does not remove the data. However, it clears the FAT/MFT so the OS cannot identify the files and for practical purposes the data is lost. It may be possible for a data recovery service to restore some of the files but it is very expensive.

[Shinma]

Additional info. at following link,

• Formatting a Hard Disk Drive

[Train]

Good find Shinma!!

Got curious and found these eraser tutorials.
Protect your privacy with Eraser,
Install:
http://www.top-windows-tutorials.com/eraser.html

Choosing and setting the wiping mode
http://www.top-windows-tutorials.com/Eraser-modes.html

Shredding files
http://www.top-windows-tutorials.com...-wipe.htmlhtml

Eraser Home Page!
http://eraser.heidi.ie/

[SuperSparks]

Also note that even overwriting a file does not render it completely unrecoverable, it just makes the data expensive to recover. Which is why government standard erasing utilities such as those Train linked to will overwrite data many times.

To answer he question of what is and isn't recoverable using standard recovery utilities, it is pretty much impossible to say, all you can do is to use a utility and see. It really depends on exactly what has been overwritten or not.

[Train]

Of interest in Shinma's link is "Old hard drives yield data bonanza" which is at the bottom of the page.

[jerryctx]

If you are really paranoid, use the fed's required procedure for destroying top secret files:

1. Remove the disk drive from the computer
2. Sandblast the disk(s) until the magnetic coating has been removed
3. Crush the disk(s) until only a fine powder remains

This is currently overkill (so far as we know) but who knows what recovery techniques will be developed tomorrow.

All of which is irrelevant to Jalal's question. As Supersparks said the only way to know what can be recovered is to try one of the recovery programs such as these:

http://www.pcworld.com/downloads/col...ads/files.html

[SuperSparks]

Recuva is very easy to use, and gives a very clear, and usually accurate, idea of which files can be easily recovered or not:

Recuva

[jerryctx]

And it is a good idea to download the recovery program before you need it. The download could overwrite the file(s) you are trying to recover!

[SuperSparks]

And it is a good idea to download the recovery program before you need it. The download could overwrite the file(s) you are trying to recover!

A very good point. Though with Recuva at least you can run a copy from a flash drive if necessary.

[Eeyore]

When files are written to a drive with data on it they are often broken up and tend to be scattered all over the drive. If you have recently run Defrag the pieces are on the drive together in sequence. In that case they can be recovered relatively easy by a recovery program as you don't need an index to tell where all the pieces are.

[jalal]

It means there's no way to say its possible or impossible... means you can recover yr data and its not deleted when we even formate our drives...

Very strange ... lol that's funny to say crush yr disk till the white powder comes outta it

Reading all yr replies... i come to know you folks yr self not sure what's the end?

All i can do is to try hell of available softwares to recover the data with different tricks ... its very difficult..

so the bottom line from this discussion is ... Data never lost.... no matter what ever you do with disk... unless you crush it to powder...

Thanks for sharing yr views and comments... all you all are highly appreciated

thanks for your time

Jalal!!

[SuperSparks]

Crushing to powder is a bit further than is really necessary, smashing the platters, or drilling holes through them renders the drive just as unreadable. In reality, though, using a secure deletion program such as Eraser is adequate for 99.9% of occasions. Only law enforcement agencies would have the specialist equipment, and the time and budget, to recover data that has been properly overwritten. That kind of forensic data recovery is incredibly time consuming and expensive, and requires very costly specialist hardware to do.