Abhinav said:
I bought a new Segate 500GB SATA hard disk, connect it externally through
USB. It worked fine for some time and then someone borrowed it.
Now I cant get to read the data in it.
My windows detects it but says...0 mb used and 0 mb free.
I have some important data in it and I seriously need to recover that.
Can someone help?
Try TestDisk. TestDisk will scan the hard drive, and try to find
a file system. It will prepare a new set of values for the Partition
Table, based on the file systems it can find. Don't accept them just yet!
Report what you see from the tool instead. Just use "Quit" for now or
press Control-C to stop the program. The purpose of doing this, is
to see if the basic structures of a file system are present.
A tool which can display the primary four entries of the Partition Table
is this one. Select the (broken) disk, then write down all the numbers
you see. By writing down the numbers, you're saving the info for later.
If you use TestDisk to overwrite the partition table, then having
the original numbers can be used to undo the changes.
PTEDIT32 for Windows
ftp://ftp.symantec.com/public/english_us_canada/tools/pq/utilities/PTEDIT32.zip
PTEDIT32 screenshot
http://www.vistax64.com/attachments...n-partiton-recovery-dell-xps-420-dell-tbl.gif
TestDisk is an example of a "repair in place" tool. In the same
sense that "chkdsk" is a "repair in place" tool. These are tools
that write to the disk. What they do, is irreversible.
Whenever using a "repair in place" tool, you want to make a
sector by sector copy of the drive having the valuable data first.
You also want a place to store any recovered data.
In other words, if a person has a 500GB drive with valuable
data, I recommend buying *two* spare hard drives while doing
data recovery. One of the spare hard drives holds an exact
copy of the (broken) drive. The other spare drive, contains
sufficient room to hold all the recovered data (such as when
you're using a $39.95 data recovery program).
I recommend running TestDisk first, just to get an opinion
as to what is going on. Do not attempt any "write" operations
with TestDisk, unless you have that valuable backup copy made.
I copy disks in Linux, sector by sector, using "dd".
dd if=/dev/hda of=/dev/hdb
That copies the entire "hda" disk to "hdb". SATA drives may be
named "sda" and "sdb" etc. The command syntax is changed
slightly, when you move the data back to the original
disk - please post back later if you want details.
If the (broken) drive has damaged sectors, follow the procedure here.
You use a "dd_rescue" application, rather than the standard "dd",
to yield the best quality copy of the drive. This is a way of
copying the maximum amount of data from the damaged disk, and
saving it for later. If a damaged disk dies while you're working
on it, the copy of the data you make this way, is better than nothing.
http://www.cgsecurity.org/wiki/Damaged_Hard_Disk
Copies of TestDisk can be obtained here.
http://www.cgsecurity.org/wiki/TestDisk
If you don't feel competent to do data recovery,
get help at a shop.
It is possible to run "chkdsk" on a partition, using its volume
name rather than a drive letter. So if the drive did not have
a letter, there are other ways to get to it.
chkdsk M:
chkdsk \\?\Volume{2d9bd2a8-5df8-11d2-bdaa-000000000000}
(Details here)
http://technet.microsoft.com/en-us/library/bb457122.aspx
The "mountvol" utility is supposed to report the partition names
in that format. Take a (working) partition name and search the registry.
Maybe you'll get lucky and find something matching the (broken)
partition. So that is another idea you might try.
I'm an amateur home user, not a data recovery professional. It is
possible some $39.95 data recovery program will solve this problem
instantly, but I encourage a methodical approach, of at least
making a sector by sector backup first.
If you're on dialup networking, and cannot manage to boot a Linux
LiveCD for doing maintenance tasks, there is a port of "dd" for
Windows. Follow the example on the page, to learn more about
the naming conventions used in Windows. They differ from the
simpler syntax of the Linux commands. But can still be used to
do that all-important backup of the broken drive, before
you use any of the "write-in-place" repair tools.
(Good for making backups sector by sector, and it is free)
http://www.chrysocome.net/dd
Good luck,
Paul
