Everyone's Guide to Data Recovery

Why everyone's?
Because everyone is going to experience data loss someday. Its not a question of if but a question of when. This guide will focus on recovering data from devices that are otherwise functioning properly, which means devices with physical/mechanical failure/damage are excluded. There is a possibility that data can be recovered in those scenarios as well but you will probably need to send in the device to a specialised data recovery center.

The easiest way to recover your data:
Connect that external hard drive you use for your backups, fire up your backup software and copy back all the files you need.

Help, I don't have backups!
What? You don't have backups??? Now is the time to kick yourself for not taking this basic precaution. After you are done kicking yourself, go out and buy an external hard drive now. You will probably need it during the recovery process as well. Also be prepared to spend some (more likely, a lot of) money on specialised recovery software. If you have a desktop, you can use a second internal drive instead.

Common steps for all recovery strategies:
* Step back from the computer, take a deep breath and resist the urge to scream.
* Minimize (if not eliminate) all write activity to the drive/partition where the data was stored. For instance, if the data was stored in the D: drive, then do not copy any files to that drive or create new files/folders there. If the data was stored under C: or My Documents, then do not copy/create new files there and do not install new applications there. Keep in mind that even the act of starting/shutting down Windows will cause some read and write activity, so if your data was stored on C:, avoid starting/shutting down Windows until you have a detailed recovery plan.
* Make a detailed note of the circumstances of the data loss. What were you doing when the loss occurred? Try to recall the exact sequence of steps as this will help you in your recovery attempts.
* Do not make hit or miss attempts to recover your data. Analyse your situation, make a plan and some alternative plans that you would like to try, and note them down on paper before you return to your computer to try to recover your data.
* Try to arrange for a second computer and a second hard drive which you can use both to continue with your work as well as help in your attempts to recover data.

How to recover deleted files:
This is the easiest scenario to deal with and your chances of getting back your data are quite high. Remember to follow the common steps outlined above. For instance, do not download or install any software on this partition, do not save any open files on this partition, etc. Get PC Inspector File Recovery http://www.snapfiles.com/get/pcinspector.html and run it to get back your files. This should also work if you had initially moved your files to recycle bin and then emptied the recycle bin. There is an accompanying program called Smart Recovery that will recover pictures from media cards.

What to do if you trashed the partition table:
The partition table is a small data structure located in the first sector of a hard drive that specifies the location of each partition. If this data structure becomes corrupted, then Windows (or Linux, if you are using Linux) will become confused and will either tell you that there is no partition on the drive or will report partitions incorrectly. There is simply no easy way to recover from this situation, especially since there is only one copy of this critical data structure on a drive. If by some stroke of luck (or because you made a backup), you know the locations of each partition exactly, then you can find several programs that will let you edit the partition table data even if you can't boot up into your installed Windows/Linux. There is however one case that lends itself to easy recovery. If the drive in question has more than partition but you are only interested in the first partition (lets say the first partition has Windows with all your data while the second has Linux which you were playing around with), then you can use any standard disk partition tool to set up your drive with only one partition that spans the entire drive. This should make the first partition accessible so that you will be able to copy your files out of this partition. For other cases, you can still attempt a recovery but your chances of success are much smaller. You have two options: the first one uses Acronis Disk Director Suite which currently costs $50 while the second one uses Ontrack EasyRecovery DataRecovery (or EasyRecovery Professional) which costs about $400. The second method is specific to Windows but has much higher chances of success. Acronis Disk Director Suite includes Acronis Partition Recovery which will scan the drive for you and try to guess the location of each partition based on information that is commonly found at the beginning of each partition. It will be helpful to know the approximate size and location of each partition to validate the guesses that Partition Recovery makes. Keep in mind that it is especially important to be right about where each partition starts while the exact end location of each partition is less likely to be of importance. If you think the guesses are correct, Partition Recovery will set up the partition table for you with its guesses and you can try to copy your data out of the drive. If you go with EasyRecovery instead, you will need to use the option to recover from a formatted drive. EasyRecovery will then scan the drive for you and give you a list of files and folders that it found, arranged nicely in a tree structure. You can place a check mark against the files/folders you want to recover and copy them out to another location.

What to do if you formatted a drive:
You will need Ontrack EasyRecovery (either DataRecovery or Professional). You will use the option to recover data from a formatted drive to scan your drive and try to recover your files and folders. If however, you managed to format the only drive in your system (such as your laptop drive) and can't even boot up, then you are in a royal mess. You will need to physically remove the drive from your system, connect it to another system and then run recovery. You could also try to create an image of your hard drive using a program that will boot up your computer and let you create images from its own boot up environment, then mount that image on another computer to try to run recovery software on that image instead. If you are willing to shell out another thousand bucks, then you have another option. You can get Winternals which will boot up your computer and make your drive accessible over the network to another computer exactly as if it were a physical drive on the other computer and once again, this will enable you to run recovery software on the drive.

What to do if you managed to trash Windows so that you can't boot up into Windows:
If all that you have done is to damage the Windows system settings but not the filesystem structures, then you need to boot up your computer with a linux Live CD such as Knoppix. Mount the (NTFS) partition as read only and copy out the data to another drive or network location. Thereafter you can try to fix Windows by restoring/reinstalling from your system disk.

I forgot the password and can't log in to Windows:
Several programs available that will let you reset the password on a Windows system. In particular, Winternals will let you do this from an independent boot up environment so that you can get back in even if you are otherwise totally locked out of your own system.

All other cases involving Windows partitions:
Your best bet is to use Ontrack EasyRecovery DataRecovery/Professional with the option to recover data from a formatted drive option.

How do I recover deleted files under Linux:
Coming soon.

Disclaimer: I am not affiliated with Ontrack in any way. The only reason that I have mentioned their software is because it seems to work very well. They have a trial version which you can download and run. The trial will scan the disk and report all that can be recovered. If you are satisfied, you have to pony up the money to get the full version which will actually do the recovery. The trial version will also let you save the results of your scan so that you can start recovery as soon as you get the full version.

Note: It seems that Winternals has been acquired by Microsoft and is no longer available.