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How do I recover a corrupt system file if my Windows was pre-installed?


I have Windows XP home media edition. The message reads: “Windowsncould not start because the following file is missing or corrupt – <windows root>\system32\ntoskrnl.exe Please re-install a copy of the above file.” The computer came with pre-installed Windows. All I have is recovery disks. I already lost all of my data once and I cannot afford to lose it again. Please advise. I also spent hours looking for an answer on the internet. I saw nothing that could solve my problem.

I’ve addressed this and similar questions here several times before, but I want to revisit this because there are two important reminders that arise out of addressing this situation.

The first, of course, is that even if Windows is pre-installed you should always get the installation, not recovery, CDs when you buy a new machine.

Why manufacturers think it’s a good idea not to provide them automatically is beyond me.

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First, let’s run through a few possible ways you might get lucky and be able to recover that single file.

  • Boot from that recovery disk, ideally into a Windows command prompt, or boot using one of the many Linux “Live CDs”. In either case, this should allow you to explore the data on your hard drive.
  • Look for a folder labeled “I386” in the root of your C: drive – you may find a backup copy of the missing file there, or in subfolders there. (Other “I386” folders elsewhere on the hard drive are not likely to have this file, though there’s no harm in looking.)
  • Look for another partition on the hard drive – perhaps a “D:” drive. Many manufacturers place recovery data onto this other partition so that it remains untouched as you use your machine normally. The missing file might be found somewhere there.
  • Borrow a Windows installation CD from a friend and copy the required file. It’s likely that you’ll need a friend with the same version of Windows as you have.
  • Even riskier, you can try copying the required file off of that friend’s system. Once again, in the case of ntoskrnl.exe you’ll at least need the version that matches your version of Windows. In the case of other files, it’s quite possible that you’d need the version that matches your machine’s make and model as well.
“The really bad news here is that the right solution is to reinstall Windows, from scratch.”

But even if you do recover the single file, it still may not be enough.

What we don’t know is why this file went missing in the first place. The common assumption would be a virus or spyware, but perhaps it’s something else.

And perhaps more files are missing. It’s quite possible that this is simply the first of many.

The really bad news here is that the right solution is to reinstall Windows, from scratch.

And that requires an installation CD.

I would absolutely contact the manufacturer and see if they can provide you with the proper installation CDs. At this point it’s possibly even worth it to pay for them.

Failing all of the above, you can of course go out and purchase a retail copy of Windows.

It’s a mess. A mess that could have easily been avoided had the machine been provided with a matching installation CD in the first place.

Lesson #1: when purchasing a machine with Windows preinstalled, insist on getting the installation CD or DVD. There are scenarios such as this one where the original installation media is the only recovery solution.

I also want to touch on a secondary statement made in the original question: “I already lost all of my data once and I cannot afford to lose it again.”

Clearly, then, you haven’t been backing up.

If you’d been backing up regularly and thoroughly there would be no risk of losing “all of my data”. At worst you would lose the changes/updates since the last backup. How long ago that would be depends on how often you backup, and that should be a choice you make that depends on how heavily you use your computer.

I backup nightly. I’m guessing that most people who use their computers even moderately should probably do the same.

Lesson #2: backup regularly. You’ll avoid data loss when, not if, disaster strikes.

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12 comments on “How do I recover a corrupt system file if my Windows was pre-installed?”

  1. This is an excellent example of why you should NEVER store your personal stuff on the Windows drive. If the main drive crashed, you would still have your data saved on an external drive. Not to mention that the main drive doesn’t get as fragmented as you add files to the external drive.

  2. “You should ALWAYS get the installation disks”?

    Are you KIDDING? Have you TRIED buying a Toshiba laptop in the last 5 or 10 years? They NEVER come with installations disks. And I’m pretty darn sure that the last HP laptop I bought didn’t have them either….

    No, I’m not kidding. That’s why I say insist on installation CDs or purchase your computers elsewhere. That’s the only way companies will get the message.

    – Leo
  3. Should we not, perhaps, all be lobbying our Congressmen, MPs, etc. to get it made a legal requirement for OEMs to supply installation disks with machines that have pre-installed Windows?
    In my opinion more regulation and more government is not the answer. Consumer awareness translating into consumer demand is.
    – Leo08-Oct-2008

  4. Leo,when you covered no installation disk supplied in the past didn’t you say if you have the I386 folder(on my machine 461Kb)you could re-install winxp from that or did I misunderstand you
    Kind regards Bp

  5. if your computer was pre-installed and your manufacturer did not provide you with an installtion cd of windows [recovery disc] and something goes wrong like the case above then you dont need any installation cd to reinstall windows . the copy of windows is in hidden partition on the hard drive . to start reinstall windows from the hidden partition you need to type on the f11 [ it may be differnt from atoher version of windows ] key right when you start your computer and in few seconds you can get access to recovery options

    That approach only works if the thing going wrong was not your hard disk failing. If the recovery information is on a hard disk that you can no longer access, you need an installation CD.

    – Leo
  6. I do a lot of new computer setups for people and I have noticed that if a computer comes without the operating system on disks, it also has a recovery partition, and in the quick setup guides it mentions creating recovery cds or dvds with a program provided by the computer manufacturer. I usually run this program before doing anything else. I hope this helps users.

  7. Leo, you insist on OS CD. I have many clients who purchased Barnded systems both laptops & desktops. They came with the stickres (CD Keys) and I386 folder across the partition.
    I agree with Randy’s comment on October 8,2008. I dont know where Randy is from but I am in India

  8. i have pre installed windows xp sp2 but my windows
    will be currept. when i login my wondows then system login again by again. i don’t want loos my data and i don’t want format my system and also i want edit registry tell me what can i do.

  9. all i get is a blue screen. when i turn off and turn on it says windows failed to start it gives me the options of launch startup repair or start windows normally neither works what should i do

  10. Leo, I have HP Pavilion a800N computer (a few years old now) and my CD and DVD drives recently stopped working. My investigations revealed that the driver is either missing or corrupted. All attempts to fix this so far (using programs such as Driver Medic) have all been unsuccessful; message I get is that this is a system driver, and can’t be downloaded from the net. I don’t have the restoration CDs — and couldn’t use them if I did — but I do have a D drive partition with system recovery files. Other than the CD/DVD drives my computer is operating normally. Can I access the D drive to just recover the driver(s) for the CD/DVD drives without impacting the rest of the computer? FYI, I have backed up all my data.


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