Disk crash data recovery

The list is as follows

As of 2010, virtually all of the world's Hard Disk Drives are manufactured by just five large companies: Seagate, Western Digital, Hitachi, Samsung, and Toshiba.

Now to the Fun Stuff

Whether we are building our own computer, upgrading our existing PC or just adding an extra hard drive to increase storage, we usually rely entirely on Windows for maintenance and care of this new or old hard drive. That's not always as efficient or good as it sounds. If you have ever used the Windows defragment software to defrag your hard drive, you know just how tedious and long this process is. The Defrag program itself is not very intuitive and has very few adjustable parameters.

Defragmenting is good!

It is usually a good idea to download a non Windows defragmenter with more user friendly options such as quick defrag, data map (for seeing what chunks of data are being moved) or selectable defragment options which allow you to choose what to defragment. What you select as your program of choice is entirely up to you. Be advised, however. Microsoft has been
steadily working you away from having any control over how you
defragment your drive.

With each upgrade and revision of Windows, you see less and less of what is actually going on with your hard drive, which places all of your trust on a company most people know very little about.

If you are like me, your hardware is important to you, and you want to know more, not less about what may be going wrong with your equipment. Why defrag doesn't automatically run when your hard drive slows down due to severe fragmentation is a mystery I have never solved.
Your antivirus will stop a program from destroying data, your Desktop has an automatic cleanup wizard, and even your Email asks if you want to compact messages to save space. So why does Windows allow your hard drive to fragment itself to such a state that data loss can occur simply
because Windows can no longer remember where your files are stored?

Well, those problems won't be solved by wishful thinking, we have to take control and do this ourselves. Some good defragment programs will have a scheduler, and you will want to set this up to run at a time when you will not be busy on your PC. Remember to disable screensavers as this will slow down your defrag speed. Some antiviruses can do this as well, especially if they just happen to update you while the defragmenter is running. Essentially Any program that writes data to your hard drive while you are trying to defrag it will slow down your completion time, so turn it off.

Scandisk or Checkdisk

CHKDSK (short for Checkdisk) is a command on computers running DOS, OS/2 and Microsoft Windows operating systems that displays the file system integrity status of hard disks and floppy disk and can fix logical file system errors. It is similar to the fsck command in Unix.
On computers running NT-based versions of Windows, CHKDSK can also check the disk surface for physical errors or bad sectors, (an area of the disk that may have had a momentary head
crash) a task previously done by SCANDISK (for older versions of Windows such as, 95,98,ME).

This version of CHKDSK can also handle some physical errors and recover data that is still readable.

When do you run scandisk?

1. When data loss has occurred, typically when Windows cannot find a file.
2. When your computer can actually find the file, but takes forever getting there.
3. When your PC is using a hibernation file as well as system restore and cant restore properly.
4. When your PC continually starts up in safe mode.
5. When you get an error stating that Windows must shut down to prevent data loss.
6. After a virus is detected and cleaned.

Windows does not perform this check automatically or when an error occurs. In some instances such as several hard starts or crashes, Windows will offer to run the scandisk or start itself, but by then it is usually too late to actually do any good. While it may make you feel better that the Disk check program has started on it's own, and it appears that Windows is trying to protect you from data loss, the actual fact is that this is a last ditch effort for Windows to recover itself, not your data, but it's own startup files. If your data gets saved in the process, so much the better.

Alternately you can run Scandisk-Checkdisk in the Shell mode or dos type box.
CHKDSK can be run from the Windows Shell, the Windows Command Prompt or the Windows Recovery Console. One option for CHKDSK is the use of the Command-line/R parameter, which allows the program to repair damage it finds on the hard drive.
Conducting a CHKDSK can take some time, especially if using the /R parameter, and the results are often not visible, for various reasons. The results of a CHKDSK conducted on restart using Windows 2000 or later operating systems are written to the Application Log, with a "Source"
name of Wininit or Winlogon and can be viewed with the Event Viewer.

This method is usually your last line of defense and will only be offered in extreme situations where a boot failure has occurred.

A word on SFC (System File Checker)

Have you ever had a program fail to execute, then follow with a DLL error of some type? This is a handy way to restore that corrupt, missing or virus altered DLL, and it can be started in Windows.
By default, Windows File Protection is always enabled and allows Windows digitally signed files to replace existing files safely. Currently, signed files are distributed through:

# Windows Service Packs
# Hotfix distributions
# Operating system upgrades
# Windows Update
# Windows Device Manager

If you introduce a file replacement in any other way, Windows File protection will overwrite your file! An important part of Windows File Protection is the command line utility:

System File Checker (sfc.exe)

Use this utility when you suspect there may be a problem with a Windows XP system file. To do this simply go to the Run box on the Start Menu and type in: sfc /scannow.