Steps to recover Lost Data from Hard Drive..

Here is some important information about recovering your lost files or data from hard drive.
Last week I lost some part of important data and was knowing the exact steps to recover,But still managed to recove almost all the data :-)
Even below are not the exact steps to recover data but at least you can prvent further damage and can recover some part of it !


The number one rule to follow when you havelost data is to not write anything more to the affected hard drive! This rule stands true for any situation...
If you have deleted a partition by accident, do not create another partition, just leave it blank.
If you have deleted files from the recycling bin that you realize you need, do not (if possible) save anything to the drive. The reason for this is that hard drives do not actually erase anything, not data or partitions. When you erase a file from the operating systems, it is just marked on the drive as having been deleted. When the system needs to store more data on the drive, it will consider files on the drive marked 'deleted' as being empty space, and cheerfully copy over them. If that happens then you're in big trouble.
The same rule applies twice over for partitions; since partition information just presents the operating system with a way of addressing the space available on the drive. If you wipe out a partition everything from it will seem to be gone.
So if there is no partition information, no data can be read by the operating system. This does not mean that your data it is not there however, only that you can't see it. Data-recovery programs have no such handicap.
What I had done in my zeal was to allow FDISK to test the integrity of the drive, which it does by writing a pattern of data to certain areas. Of course, in my case, many of these areas contained partition information and/or critical system files. The result was one missing partition, due to a destroyed boot sector, and one unbootable (but still readable) XP installation. The good news? I got it (almost) all back.
Here's how.
The first, and best thing to do in a data-loss situation is to make sure no more data is written to the drive. Obviously, if you have just the one partition and it's fried, you can't boot normally to the operating system. The best option in this situation is to transfer the drive to another computer, preferably one using the same file-system as your damaged partition (i.e. the same operating system, or a newer version).
Transferring the HDD to another computer has the dual benefit of preventing the drive from being written to accidentally, and potentially allowing you to retrieve information from the disk just by using Windows Explorer to look through file structures.
If you have damaged or erased essential operating system files, but the partition information is still intact Windows will not boot. The HDD can still be read from a different operating system which is one way out of the doom and gloom.
This was the case with one of the two XP partitions on the disk I mangled, as I was able to fully access it after moving the hard disk physically to another computer.