I keep getting the "error loading operating system" message when WinXP restarts during it's installation. I've also tried installing Win2000, with it only repeating the same message. I switched hard drives from an HP computer. Does this have anything to do with it?

I am getting the same message after I flashed the Bios of my P2B-DS motherboard to version 1014. My SCSI hard drives are detect properly but windows XP give me an "Error loading operating system" message. I booted on the CD and ran fixboot and fixmbr from the console to no avail. I am gessing that when the ESCD was erased because of the flashing, the OS was not able to cope with it when it came to booting.
Anyone knows how to recover my OS?

I have a WD1200JB that has been purring along happily as my secondary hard drive (primary slave) for several months now. Recently I had the time to try to clone my drive or install XP Pro on ths drive. I tried to Ghost it and all I get now is "error loading operating system" after the mainboard boot-up stuff is done. Tried the fixboot and fixmbr, no luck. I noticed fixmbr tells me I have a non-standard or corrupt MBR, which seems odd.

I tried formatting the drive during XP installation from CD, same symptom. Next I deleted the partition and tried installing XP with the same result. I did a low-level format (write zeroes) to the first 20% of the drive using WD DataLifeguard diagnostics but after I started the XP install I got the same error message after the first reboot just like always. I may try letting the low-level format run the full length but on such a large drive I estimate it will take over 24 hours.

Scoured MS knowledge base. Scoured WD knowledge base. Searched on google. That's how I got here. So far nothing has helped. I'm hoping someone might stumble across this and offer something helpful. I will continue to scour and I shall return if I stumble across anything useful

Nothing on the first 12 pages of google hits really helped much. By trial and error I found in my case that by selecting LBA mode instead of CHS mode in the CMOS setup fixed the problem. Hopefuly that might help you folks with the similar problems.

I have found a solution that actually works to this problem, but you have to use Western Digital's program and do the low-level format that writes all 0's to the hard drive. If you try to install XP, you will get the same problem again, and you will have to start over. I hear the problem has to do with VIA chipsets mostly, and conflicts in them with XP and 2000. If you install Windows 98 and upgrade to XP or 2000, this solves the problem. It worked for me so you might try it out. :)

I found a simple solution today (Sept.5, 2002). I downloaded from bootdisk.com a software called XP Boot. It has a newer version of fdisk on it. After getting the error message, I ran fdisk /mbr and killed the master boot record. I then restarted the machine and it booted right up. Hope this works.

Steven Nerenberg, you are a star. fdisk /mbr fixed it all up for me... I think I screwed my MBR up when playing around with my raid devices... I had tried replacing my mbr, but it obviously didn't fix it properly. It is a shame that I thought I had to format my computer and didn't do this fdisk /mbr before that :) But I am happy now that it works. I also had just flashed my bios and I thought that may have been something that caused my problem.
Thanks again!
Matt

I tried all the fixes you guys came upi with but it still doesn't work. Have any other ideas?

"I have a WD1200JB that has been purring along happily as my secondary hard drive (primary slave)"

XP Hates not being on the primary master. Try putting this drive in that slot and see what happens. I had a problem similar to this and this fixed the problem for me. Just a guess, but it can't hurt.

Trying to install XP on an abit BP6 dual 433 celeron with Samsung SV6004H
(60GB) on primary master of onboard IDE (not the HPT366). Installation
goes OK for the first part (copying files to hd) (I tried FAT, NTFS and
installing on a partition smaller than 2GB (2040MB). Then, after reboot, I
get:

Error loading operating system

Then I try to boot from install CD and the install CD does not give me
the option of restoring an existig version of windows. Recovery option R
allows me to do some further investigations: running FIXMBR tells me:

This computer appears to have a non-standard or invalid master boot record.
[...]

I say yes. But that solves nothing. Rebooting gives the same error as
above. Then I use xpboot disk from bootdisk.com to do an fdisk /mbr, and
then I get:

Missing operating system

for the NTFS install, and

invalid BOOT.INI file
Booting from C:\WINDOWS

then the machine automatically reboots for the FAT installation. If I run
FIXMBR from this point, I get the "Error loading operating system" error
back again.

I even tried to make the partition with fdisk from the xpboot disk, with
the bios HD setting to LBA and installing XP with FAT that way, but I get
the exact same problem ("Error loading...").

Things I have tried:

- win98 runs fine on the computer/hd.
- installing XP on 10GB partition NTFS, 57GB NTFS, 2GB NTFS, 2GB FAT
- upgrading the bios to version RU and to RU without HPT366
- changing bios setting to use straight CHS or LBA translation
- using fdisk /mbr from xpboot from bootdisk.com

Things I want to still try:
- make sure win98 boots all rigth doing a sys a: c: from xpboot disk
- try all of the above with win2000

Any suggestions of other things I should try? Thanks.

I had the same problem in win2k(my disk - Maxtor / 40Gb / 4D040H2). I tried a lot of things. Finaly helps this:
1. Download Powermax from maxtor.com
2. Run it - perform low level format
3. In bios setup select LBA mode for disk
4. Install win2k

It takes time but it works. Forget about data you had on your computer, if you will work this way.

I couldn't get winXP on my PC(K6/2, 40GB WD) I tried most of what is listed above but it wasn't until I did the low level format and reinstalled that it worked ok.
Try what Vlado suggests it worked for me.

i was doing a disk to disk copy using powermax 2 (20gb and 40gb maxtor disks)
and it crashed and trashed the mbr on my existing disk so beware.
also having same problem 'error loading OS' on trying to install xp/2000 on 40gb maxtor

I just cracked this by doing a low level block format using maxllf and reinstalling win2000 pro with a FAT32 partition and i finally got the installation proceeding after numerous attempts.