This computer is only a few month old! I do not know what to do. I have tried to reboot in safe mode and still are redirected to blue screen with this error. Any help would be apprecitated. I am on another compter now. original title: Blue Screen help for Windows 7! Stop: c000021a {Fatal System Error} The initial session process or system process terminated unexpectedly with a status of 0x00000000 (0xc0000221 0x001003a8). The system has been shut down.

Hi, STOP: 0xC000021A Cause This error occurs when a user-mode subsystem, such as WinLogon or the Client Server Run-Time Subsystem (CSRSS), has been fatally compromised and security can no longer be guaranteed. In response, the operating system switches to kernel mode. Microsoft Windows cannot run without WinLogon or CSRSS. Therefore, this is one of the few cases where the failure of a user-mode service can shut down the system. Mismatched system files can also cause this error. This can occur if you have restored your hard disk from a backup. Some backup programs might skip restoring system files that they determine are in use. Resolving the Problem Running the kernel debugger is not useful in this situation because the actual error occurred in a user-mode process. *Resolving an error in a user-mode device driver, system service, or third-party application:*Because bug check 0xC000021A occurs in a user-mode process, the most common culprits are third-party applications. If the error occurred after the installation of a new or updated device driver, system service, or third-party application, the new software should be removed or disabled. Contact the manufacturer of the software about a possible update. If the error occurs during system startup, restart your computer, and press F8 at the character-based menu that displays the operating system choices. At the resulting Windows Advanced Options menu, choose the Last Known Good Configuration option. This option is most effective when only one driver or service is added at a time. If this does not resolve the error, try manually removing the offending software. If the system partition is formatted with file allocation table (FAT), use an MS-DOS startup disk to gain access to the computer's hard disk. If the system partition is formatted with NTFS file system, you might be able to use Safe Mode to rename or delete the faulty software. If the faulty software is used as part of the system startup process in Safe Mode, you need to start the computer using the Recovery Console in order to access the file. If a newly installed piece if hardware is suspected, remove it to see if this resolves the issue. Try running the Emergency Recovery Disk (ERD) and allow the system to repair any errors that it detects. Resolving a mismatched system file problem: If you have recently restored your hard disk from a backup, check if there is an updated version of the Backup/Restore program available from the manufacturer. Make sure the latest Windows Service Pack is installed. STOP: 0xC000021A <-- read this http://www.faultwire.com/solutions-fatal\_error/STATUS-SYSTEM-PROCESS-TERMINATED-0xC000021A-\*1314.html Look in the Event Viewer to see if anything is reported about those. http://www.computerperformance.co.uk/vista/vista\_event\_viewer.htm MyEventViewer - Free - a simple alternative to the standard event viewer of Windows.TIP - Options - Advanced Filter allows you to see a time frame instead of the whole file. http://www.nirsoft.net/utils/my\_event\_viewer.html This is my generic bluescreen troubleshooter - you can try Safe Mode as suggested in the article above - repeatedly tap F8 as you boot. Vista disks are probably needed - if you do not have to try repair you can borrow a friends as they are not copy protected. Also you can buy the physical disks from the system maker cheap as you already own Windows (you will need these to reinstall if required). You can also make repair disks on another computer. Here are some methods to possibly fix the blue screen issue. If you could give the Blue Screen info that would help. Such as the BCC and the other 4 entries on the lower left. And any other error information such as STOP codes and info such as IRQL_NOT_LESS_OR_EQUAL or PAGE_FAULT_IN_NONPAGED_AREA and similar messages. As examples : BCCode: 116 BCP1: 87BC9510 BCP2: 8C013D80 BCP3: 00000000 BCP4: 00000002 or in this format : Stop: 0x00000000 (oxoooooooo oxoooooooo oxooooooooo oxoooooooo) tcpip.sys - Address 0x00000000 base at 0x000000000 DateStamp 0x000000000 This is an excellent tool for posting Blue Screen Error InformationBlueScreenView scans all your minidump files created during 'blue screen of death'crashes, and displays the information about all crashes in one table - Free http://www.nirsoft.net/utils/blue\_screen\_view.html Many BlueScreens are caused by old or corrupted drivers, especially video drivers however there are other causes. You can do these in Safe Mode if needed or from Command Prompt from Vista DVD or Recovery Options if your system has that installed by the maker. How to Boot to the System Recovery Options in Windows 7 http://www.sevenforums.com/tutorials/668-system-recovery-options.html You can try a System Restore back to a point before the problem started if there is one. How to Do a System Restore in Windows 7 http://www.sevenforums.com/tutorials/700-system-restore.html Start - type this in Search Box -> COMMAND find at top and RIGHT CLICK - RUN AS ADMIN Enter this at the prompt - sfc /scannow How to Repair Windows 7 System Files with System File Checker http://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html How to analyze the log file entries that the Microsoft Windows Resource Checker (SFC.exe) program generates in Windows Vista cbs.log (and Windows 7) http://support.microsoft.com/kb/928228 The log might give you the answer if there was a corrupted driver. (Does not tell all the possible driver issues). Also run CheckDisk so we can rule out corruption as much as possible. How to Run Check Disk at Startup in Windows 7 http://www.sevenforums.com/tutorials/433-disk-check.html Often updating drivers will help, usually Video, Sound, Network Card (NIC), WiFi, 3rd party keyboard and mouse, as well as other major device drivers. Manually look at manufacturer's sites for drivers - and Device Maker's sites. http://pcsupport.about.com/od/driverssupport/ht/driverdlmfgr.htm Installing and updating drivers in Windows 7 (updating drivers manually using the methods above is preferred to ensure the latest drivers from System maker and Device makers are found) http://www.sevenforums.com/tutorials/43216-installing-updating-drivers-7-a.html How To Disable Automatic Driver Installation In Windows Vista - Drivers http://www.addictivetips.com/windows-tips/how-to-disable-automatic-driver-installation-in-windows-vista/ http://technet.microsoft.com/en-us/library/cc730606(WS.10).aspx How to fix BlueScreen (STOP) errors that cause Windows Vista to shut down or restart unexpectedly http://support.microsoft.com/kb/958233 Troubleshooting Vista Blue Screen, STOP Errors (and Windows 7) http://www.chicagotech.net/vista/vistabluescreen.htm Understanding and Decoding BSOD (blue screen of death) Messages http://www.taranfx.com/blog/?p=692 Windows - Troubleshooting Blue Screen Errors http://kb.wisc.edu/page.php?id=7033 In some cases this might be required. StartUp Repair from Recovery Options or Windows 7 disk How to Run a Startup Repair in Windows 7 http://www.sevenforums.com/tutorials/681-startup-repair.html How to Boot to the System Recovery Options in Windows 7 http://www.sevenforums.com/tutorials/668-system-recovery-options.html How to Create a Windows 7 System Repair Disc http://www.sevenforums.com/tutorials/2083-system-repair-disc-create.html Hope this helps. Rob Brown - MS MVP - Windows Desktop Experience : Bicycle - Mark Twain said it right.

I tried to start from Last known good configuration with no luck. I can not get beyond the blue screen to do anything else.

I ran memtest and my RAM passed 5 cycles without error. I can run a linux live cd without issue & SMART reports my hard drive as healthy. Brand new power supply & motherboard. Trying to install OS I get the BSOD c000021a error every time I boot to my Windows 7 dvd. Now what?

I had this same problem with my Windows Vista OS. But I have found the solution. I know that this will work with Vista and 7 and probably other newer OS versions. There is no option for this under XP but I would run a Repair which I have outlined below. I saw this in my Maximum PC mag a while back and have used it fixing many computers since I have found it out. You want to read the 3rd step which outlines how to run "System File Checker" from off of the boot CD or from the "Repair your computer" option when you press f8 on boot. http://www.maximumpc.com/article/how-tos/how_repair_faulty_windows_installation_without_reformatting One thing that I would do before running through the procedure is running a check disk on the drive. CHKDSK C: /R This should fix the problem if it doesn't then I would run SpinRite which is 89 bucks but worth every penny. You can get that here: http://www.grc.com/spinrite.htm How to Repair XP. Boot the computer from your Windows XP CD. When you see the "Welcome To Setup" screen press [Enter] to start the Windows Setup. Note: Do not choose "To repair a Windows XP installation using the Recovery Console, press R", you Do Not want to load Recovery Console. Accept the Licence Agreement and Windows will search for existing Windows installations. Select the XP installation you want to repair from the list and press [R] to start the repair. Setup will copy the necessary files to the hard drive and reboot. Do not press any key to boot from CD when the message appears. Setup will then continue as if it were doing a clean install, but your applications and settings will remain intact. Hope this helps. uByte

help i even booted from dvd and the blue screen appears

Blue Screen Error: c000021a Fatal System Error

Answer accepted by question author

Anonymous

2010-05-04T01:07:13+00:00

Hi,

STOP: 0xC000021A

Cause

This error occurs when a user-mode subsystem, such as WinLogon or the Client Server Run-Time Subsystem (CSRSS), has been fatally compromised and security can no longer be guaranteed. In response, the operating system switches to kernel mode. Microsoft Windows cannot run without WinLogon or CSRSS. Therefore, this is one of the few cases where the failure of a user-mode service can shut down the system.

Mismatched system files can also cause this error. This can occur if you have restored your hard disk from a backup. Some backup programs might skip restoring system files that they determine are in use.

Resolving the Problem

Running the kernel debugger is not useful in this situation because the actual error occurred in a user-mode process.

*Resolving an error in a user-mode device driver, system service, or third-party application:*Because bug check 0xC000021A occurs in a user-mode process, the most common culprits are third-party applications. If the error occurred after the installation of a new or updated device driver, system service, or third-party application, the new software should be removed or disabled. Contact the manufacturer of the software about a possible update.

If the error occurs during system startup, restart your computer, and press F8 at the character-based menu that displays the operating system choices. At the resulting WindowsAdvanced Options menu, choose the Last Known Good Configuration option. This option is most effective when only one driver or service is added at a time. If this does not resolve the error, try manually removing the offending software. If the system partition is formatted with file allocation table (FAT), use an MS-DOS startup disk to gain access to the computer's hard disk. If the system partition is formatted with NTFS file system, you might be able to use Safe Mode to rename or delete the faulty software. If the faulty software is used as part of the system startup process in Safe Mode, you need to start the computer using the Recovery Console in order to access the file. If a newly installed piece if hardware is suspected, remove it to see if this resolves the issue.

Try running the Emergency Recovery Disk (ERD) and allow the system to repair any errors that it detects.

Resolving a mismatched system file problem: If you have recently restored your hard disk from a backup, check if there is an updated version of the Backup/Restore program available from the manufacturer. Make sure the latest Windows Service Pack is installed.

STOP: 0xC000021A <-- read thishttp://www.faultwire.com/solutions-fatal\_error/STATUS-SYSTEM-PROCESS-TERMINATED-0xC000021A-\*1314.html

Look in the Event Viewer to see if anything is reported about those.

http://www.computerperformance.co.uk/vista/vista\_event\_viewer.htm

MyEventViewer - Free - a simple alternative to the standard event viewer of Windows.TIP - Options - Advanced Filter allows you to see a time frame instead of the whole file.

http://www.nirsoft.net/utils/my\_event\_viewer.html

This is my generic bluescreen troubleshooter - you can try Safe Mode as suggested in the article

above - repeatedly tap F8 as you boot. Vista disks are probably needed - if you do not have to try

repair you can borrow a friends as they are not copy protected. Also you can buy the physical disks

from the system maker cheap as you already own Windows (you will need these to reinstall if

required). You can also make repair disks on another computer.

Here are some methods to possibly fix the blue screen issue. If you could give the Blue Screen info

that would help. Such as the BCC and the other 4 entries on the lower left. And any other error

information such as STOP codes and info such as IRQL_NOT_LESS_OR_EQUAL or PAGE_FAULT_IN_NONPAGED_AREA and similar messages.

As examples :

BCCode: 116

BCP1: 87BC9510

BCP2: 8C013D80

BCP3: 00000000

BCP4: 00000002

or in this format :

Stop: 0x00000000 (oxoooooooo oxoooooooo oxooooooooo oxoooooooo)

tcpip.sys - Address 0x00000000 base at 0x000000000 DateStamp 0x000000000

This is an excellent tool for posting Blue Screen Error InformationBlueScreenView scans all your minidump files created during 'blue screen of death'crashes, and displays the information about all crashes in one table - Free

http://www.nirsoft.net/utils/blue\_screen\_view.html

Many BlueScreens are caused by old or corrupted drivers, especially video drivers however there

are other causes.

You can do these in Safe Mode if needed or from Command Prompt from Vista DVD or Recovery

Options if your system has that installed by the maker.

How to Boot to the System Recovery Options in Windows 7

http://www.sevenforums.com/tutorials/668-system-recovery-options.html

You can try a System Restore back to a point before the problem started if there is one.

How to Do a System Restore in Windows 7

http://www.sevenforums.com/tutorials/700-system-restore.html

Start - type this in Search Box -> COMMAND find at top and RIGHT CLICK - RUN AS ADMIN

Enter this at the prompt - sfc /scannow

How to Repair Windows 7 System Files with System File Checker

http://www.sevenforums.com/tutorials/1538-sfc-scannow-command-system-file-checker.html

How to analyze the log file entries that the Microsoft Windows Resource Checker (SFC.exe) program

generates in Windows Vista cbs.log (and Windows 7)

http://support.microsoft.com/kb/928228

The log might give you the answer if there was a corrupted driver. (Does not tell all the possible

driver issues).

Also run CheckDisk so we can rule out corruption as much as possible.

How to Run Check Disk at Startup in Windows 7

http://www.sevenforums.com/tutorials/433-disk-check.html

Often updating drivers will help, usually Video, Sound, Network Card (NIC), WiFi, 3rd party

keyboard and mouse, as well as other major device drivers.

Manually look at manufacturer's sites for drivers - and Device Maker's sites.

http://pcsupport.about.com/od/driverssupport/ht/driverdlmfgr.htm

Installing and updating drivers in Windows 7 (updating drivers manually using the methods above

is preferred to ensure the latest drivers from System maker and Device makers are found)

http://www.sevenforums.com/tutorials/43216-installing-updating-drivers-7-a.html

How To Disable Automatic Driver Installation In Windows Vista - Drivers

http://www.addictivetips.com/windows-tips/how-to-disable-automatic-driver-installation-in-windows-vista/

http://technet.microsoft.com/en-us/library/cc730606(WS.10).aspx

How to fix BlueScreen (STOP) errors that cause Windows Vista to shut down or restart

unexpectedly

http://support.microsoft.com/kb/958233

Troubleshooting Vista Blue Screen, STOP Errors (and Windows 7)

http://www.chicagotech.net/vista/vistabluescreen.htm

Understanding and Decoding BSOD (blue screen of death) Messages

http://www.taranfx.com/blog/?p=692

Windows - Troubleshooting Blue Screen Errors

http://kb.wisc.edu/page.php?id=7033

In some cases this might be required.

StartUp Repair from Recovery Options or Windows 7 disk

How to Run a Startup Repair in Windows 7

http://www.sevenforums.com/tutorials/681-startup-repair.html

How to Boot to the System Recovery Options in Windows 7

http://www.sevenforums.com/tutorials/668-system-recovery-options.html

How to Create a Windows 7 System Repair Disc

http://www.sevenforums.com/tutorials/2083-system-repair-disc-create.html

Hope this helps.

Rob Brown - MS MVP - Windows Desktop Experience : Bicycle - Mark Twain said it right.
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