Missing Operating System

Again? Is it doing it a lot? Just lately? Hmmmmm.... If you get a catastrophic failure like this, you need to find out why it happened. A virus, hard drive failure, some other hardware failure?

Here's what I would do, in order, before I gave up & decided to start again.

1. Switch off, remove power lead, open computer case, check the hard drive IDE or SATA cables for correct and good connection at each drive and where they plug into the motherboard. Also hard drive power connector.

2. If that did not work, if you have a floppy drive, make or get a boot floppy (Look it up on Google) that is the right one for your brand of Windows and try the steps on this page:-

http://www.computerhope.com/issues/ch000181.htm

Or another page that you found by typing Missing operating system into Google.

Then, last of all,

3. If you have a bootable Windows XP install CD then study the instructions for a Windows XP repair install on a page such as

http://helpdesk.its.uiowa.edu/windows/instructions/repairinstall.htm

Or another page that you find when you type xp repair install into Google.

If you did this last one, (Or if you did a brand new install) you would need to get your Windows updates, service packs, etc up to date before you connect to the internet, or you might well get a worm, and then you'd be back where you started... You need Service Pack 2 at least.

It's not a virus or anything.
The drive temp was 28 degrees C so it wasn't overheating.

The last time something like this happened it was on an old 120 gig drive that had had problems in the past and was really only clinging to life by the skin of it's teeth.
In fact I'm using that drive now after I reformatted it and installed XP on it so I can get back onto the web on the main machine rather than my Mac laptop.

What I would really like to know is what causes that 'missing operating system' error ?

I reset the machine after it stopped responding. The drives were not running so I think the probability of something being written to the boot sectors when i ditched the power was minimal.

So what causes it ?

I've got GetDataBack going over the drive now so I'll see what happens.
I've also run a thorough scan of the drive from BartPE and that reports nothing wrong with it at all.
Says it's not formatted and there's nothing on there.
It looks like the entire boot section of the drive has disappeared along with the partition information.

There's 210 Gb of data on the disk so it's going to take me a while to get this thing back together again. I'd just really like to know what may have happened.
To give me a direction to go in so I can start looking for something.

That's a point actually.
I've tried the Repair thingy off the XP disk and all it gives me is a prompt.
It doesn't repair a damn thing.
So what's it supposed to do ?

The most likely cause of the missing operating system error is that the master boot record is corrupt due to hard disk errors or virus infection.

This can be fixed in the Windows Recovery Console. (This is not the same as a Repair Install, I'll get to that in a minute). Reading your last post, I think you got to the Recovery Console prompt, but here it is anyway:-

1. Boot off the XP install CD

2. In the "Welcome to Setup" screen, the 2nd option is "To repair a Windows XP installation using Recovery Console, press R"

3. Press R

4. When the Recovery Console opens, it will list the windows installation(s) that it found, and ask you which one you want to repair. If you only have the one installation, which would be number 1, enter 1.

5. Now it wants the Adminstrator password (if you have set one, if not, press ENTER, (I think))

6. Now you get the prompt. It's like a chopped down DOS prompt. You can type "help" to get a list of commands, and the name of any command followed by /? to get help on that command for example dir /?

Try these two first:-

FIXBOOT

FIXMBR

If there is a problem with the Boot-sector on the C:-drive, you can use "fixboot" to write a new boot-sector.

If there is a problem with the Master-Boot-Record of the disk (maybe damaged by a virus), you can use "fixmbr" to write a new MBR. This is the one I am thinking you need...

If you want to check the disk, you can use "chkdsk" to check the disk for errors like this

CHKDSK C:

chkdsk drive /p /r

The chkdsk command checks the specified drive and repairs or recovers the drive if the drive requires it.The command also marks any bad sectors and it recovers readable information.

You can use the following options:

/p : Does an exhaustive check of the drive and corrects any errors.
/r : Locates bad sectors and recovers readable information.


Note If you specify the /r option, the /p option is implied. When you specify the chkdsk command without arguments, the command checks the current drive with no options in effect.

After you get the prompt back, read any reports and messages and type EXIT to reboot the computer. If the repair worked, this is when you find out. You may need to remove the CD or change the boot order in the BIOS when the reboot happens.

--------------------------------------------------------------------------------------------------

Windows Repair Install

XP Repair install (Different from above)

1. Boot from the Windows XP installation CD

2. Press ENTER when you see the message To setup Windows XP now, and then press ENTER displayed on the Welcome to Setup screen.

3. Do not choose the option to press R to use the Recovery Console.

4. In the Windows XP Licensing Agreement, press F8 to agree to the license agreement.

5. Make sure that your current installation of Windows XP is selected in the box, and then press R to repair Windows XP.

6. Follow the instructions on the screen to complete Setup.

Blaster worm warning: Do not immediately activate over the internet when asked, enable the XP firewall before connecting to the internet. You can activate after the firewall is enabled. Control Panel - Network Connections. Right click the connection you use, Properties and there is a check box on the Advanced page.

If your install disk was pre - SP2 you will need to redo that.

I'll give the recovery a shot when GetDataBack has finished copying off my essential data.
Ohhh man there's a lot of it !

I did a chkdsk from BartPE and it reported that the check could not be performed because the drive was raw.

I wasn't aware of the fixboot etc... things from the XP disk.
That's the next thing I'll try when this is done.
I really don't want to format this drive so I'm hoping.

Thanks Contrex, it's much appreciated.

Sometimes CHKDSK reports a "raw" filesystem because the MBR is damaged, doing a FIXMBR in the Recovery Console might fix that.

Also the boot sector might be damaged, and FIXBOOT can address that. If there is no damage elsewhere, recovery should be possible.

so if you did

FIXMBR

then

FIXBOOT

that might bring back the filesystem. (Which was?? FAT32? NTFS?)

CHKDSK (with no options, so it just reports errors but does not try to fix them) should provide useful information at this point.

It was definitely FAT32 I only use NTFS when I have to.

Still dragging data off the drive at the mo. It's taking ages.
That's what I get for having zillions of gigs of data habging around the place.

I'll do the MBR then the boot when it's done.

With me, it's the reverse. The 2 Gb max file size in FAT32 is the main reason.

Good point.
I only do it for compatibility reasons really.

Okie cokie.
Did FIXMBR and it fixed it.
Did FIXBOOT and it fixed that too.
Did CHKDSK and it reported that :
"The volume appears to contain one or more unrecoverable problems".
Bummer.

Just restarted after that and now it says :
NTLDR is missing.

I have no idea what that is.
Any clues before I format this thing ?

Depends on what its worth to you; Steve Gibson's SpinRite 6 ain't free, but its pretty damned good at salvaging scrambled drives.

It's the boot loader program for the OS.

Ntldr is the name of the file stored on the hard drive that begins the process of loading the operating system for Windows NT/2000/XP.

If you got like "NTLDR missing" don't worry you need not to format your window if you have Linux.If you i already installed linux on your computer then just boot linux and paste NTLDR from someone else computer.You got NTDLR from c:\ .For this first go to Tool->folder opetion->view then uncheck the "hide protected operating system.........." they you see ntldr.sys in C:\ directory copy this and paste this in your computer by use of linux.
If you don't have linux then fist installed it.But if don't have already installed linux on your system then it is better to installed Windows again rather then linux then windows.