"Blue Screen Error STOP: C000221 Unknown Hard Error" comes when PC starts...

Hi friends !

I am having a serious error in my machine. I have a PC (Dell PC). Windows XP Professional is installed on it. Previously it was working. BUT...

now when I start the PC, I find the following error on the BLUE SCREEN...

STOP: C000221 Unknown Hard Error

and the PC doesn't boot. I  tried many times but the same error is coming.

Then I used Winternal's ERD Commander 2003 but it giv
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JatinHemantAuthor Commented:
...extremely sorry for the incomplete query...

When I use the Winternal's ERD Commander, it says that Do not attah to a Windows Installation...

It doesn't find the OS...

Please help me in this regard because I failed to overcome with the error...


JatinHemantAuthor Commented:
Dear friends !

My problem is urgent. If anyone has faced the same problem then please help me in this regard...


make sure you provide the correct error code. And any others information show in the blue screen ??
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In addition, you may have a flakey hard drive or other hardware issues.

Download the Dell diagnostics and run them.

for the hard drive see

http://www.hitachigst.com/hdd/support/download.htm               Drive Fitness Test
http://www.maxtor.com/en/support/products/index.htm               Maxtor & Quantum
http://www.fcpa.fujitsu.com/support/hard-drives/software_utilities.html#diagnostic Fujitsu
http://www.samsung.com/Products/HardDiskDrive/utilities/shdiag.htm     Samsung
http://www.seagate.com/support/seatools/index.html               Seagate
http://support.wdc.com/download/#diagutils                    Western Digital
http://www.hgst.com/hdd/support/download.htm             IBM & Hitachi  DFT

To access data, put the drive in another machine as a slave ( set jumpers if needed) and backup your data.

Another option is to use a USB adapter on the drive.

I hope this helps !
In addition to the good suggestions above, I would recommend that you create the following bootable CD's on another computer, and use them to diagnose the current problem:

(1) UBCDwin  http://www.ubcd4win.com/
(2) Bart PE CD: http://www.nu2.nu/pebuilder/
(3) UBCD: http://www.ultimatebootcd.com/

If you can confirm that your disk is Ok then you should consider a repair install of XP:


try running chkdsk / f on the drive from the recovery console :
Microsoft KB Aritical for your problem>


It looks like you need a new copy of ntdll.dll.

Some of you experts may remember how to restore critical system files like the NTDLL.DLL file. My memory is shot and I haven't done it in a while.  

If you can boot to a boot disk, I recommend you hunt down important files you want off that drive and try to put them on some sort of media before you accidentally destroy all data by trying to repair an OS. Repairing an OS doesn't work all the time.  
JatinHemantAuthor Commented:
Hi friends !

Thanks for your replies. BUT My problem is still there. The Hard disk is not faulty. I have made a surface scan.
I format the machine and made two partitions. When I tried to install a fresh copy of Windows XP Profeesional SP2, it gave the same error. Then I installed Windows 2000 Professional and I succeeded.

When I tried to upgrade it from WIndows 2000 Professional to Windows XP Professional, the same error came again. (It is a blue screen error, please see my frist post)

The specifications of my DELL PC are as followings:

Manufacturer: DELL Computer Corporation
Model : DIM4400
System Type: x86 Based PC
Processor: x86 Family 15 Model 1 Stepping 2 GenuineIntel 1595 Megahertz
BIOS version: 01/08/02

My problem is that when I installed Windows 2000 Professional, it only took the driver for LAN.

The NIC is Macronix MX98715 Family Fast Ethernet Adapter (ACPI)

I am connected to internet and can download drivers. I usually download drivers for hp/compaq and Intel. But for DELL driver when I surfed www.dell.com, I didn't find  drivers. Please tell me how can I find out which Graphics/Audio drivers I should download and from where I can download these drivers.

I don't have motherboard or any driver CD.

The answer is required urgently.




you have to fill in the model of pc you use here :
This is the forth computer today I have looked for a BSOD "STOP" error within the last couple days.

I am researching this and have so far concluded that thes STOP errors are a result of a faulty code written in a driver. The Processor gets to a certain point in the code and gets to a tag that has no reference. So, the computer has no where to go.

Nvidia Drivers for chipset, LAN and onboard Video have a known problem for this type of error. It has to do with XP and the Chipset/LAN driver.

So, I think you are on the right track in resolving this issue by replacing the drivers. But, I would get these drivers right from the manufacturer of the chipset or LAN card instead of companies like Dell. Dell or HP may still have the faulty driver.

There are a number of utilities to self discover what chipsets and devices you use on your computer. One is a free download from Belarc advisor. It will tell you. If you have service pack two or greater for XP and Genuine advantage installed, another great self discovery utility comes from Windows SYSinternals. There is a process utility that tell you what processes are running and what threads run them. There is also a systems information utility that will tell you everything you want to know about your system. The names of these are escaping my memory at this time. There are other third party utilities that specifically go out and find your particular components. MAYBE SOME OF THESE OF OUR COLLEGUES CAN RECOMMEND SOME GOOD UTILITIES OF THE SORT.

Once you have the CHIPSET, VIDEO, AUDIO, and LAN figured out, go get the drivers from the manufacturer of the card or motherboard. Bypass Dell, HP, and any other third party because they still may have the bumb driver.

You can google your error by typing in STOP:  C000221 and you will probably end up on Microsoft's Developer's Network Forum. This will tell you what tags and/or code is askew. I don't know that it will help you though. I am not a code writer, and realize this info is above my head.

I am going to continue to research BSOD from STOP errors.

Since you seem savy, may I just send the following as a reminder without insulting your intellegence? Disable all on-board NIC, VIDEO, and SOUND in BIOS if you are using a card instead of the on-board ports.

I hope this helps.

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