STOP 0xC000021A STATUS_SYSTEM_PROCESS_TERMINATED

	Problem when switching from kernel mode to user-mode. The Stop 0xC000021A message occurs when Windows XP switches into kernel mode and a user-mode subsystem, such as Winlogon or the Client Server Runtime Subsystem (CSRSS), is compromised and security can no longer be guaranteed. Because Windows XP cannot run without Winlogon or CSRSS, this is one of the few situations where the failure of a user-mode service can cause the system to stop responding. You cannot use the kernel debugger in this situation because the error occurred in a user-mode process. A Stop 0xC000021A message can also occur when the computer is restarted after a system administrator has modified permissions in such a way that the SYSTEM account no longer has adequate permissions to access system files and folders.
	You may receive the following error message: STOP: c000021a {Fatal System Error} The Windows Logon Process system process terminated unexpectedly with a status of 0xc0000034 (0x00000000 0x0000000) The system has been shutdown. Note The parameters in parentheses are specific to your computer configuration and may be different for each occurrence.
	If Microsoft Internet Explorer maintenance policies are being applied, you may receive a "Stop C000021A" error message on a blue screen on a Windows XP-based client computer during the logon process. Or, the client computer may restart. This problem may not occur until you log on and log off several times. You may also receive the following error message: STOP: 0xc000021a STATUS_SYSTEM_PROCESS_TERMINATED {Fatal System Error} The Windows Logon Process system process terminated unexpectedly with a status of 0xaaaaaa (0xbbbbbb 0xcccccc) The system has been shutdown.
	This article describes error messages that you may receive after you modify some security permissions on your computer that is running Microsoft Windows Server 2003, Windows XP, or Windows 2000. This article discusses how to resolve these issues on each operating system. It also discusses how to resolve a paging file issue that you may experience after you resolve the security permissions issue.
	You use a smart card for user authentication on a computer that is running either Microsoft Windows XP Service Pack 1 (SP1) or Windows XP Service Pack 2 (SP2). You insert the smart card in to the reader and type the PIN to initiate the log on process. You remove the smart card before the log on process is completed. You insert the smart card again. In this scenario, a stack corruption occurs, and the computer stops responding (hangs). Additionally, you receive the following error message: STOP: 0xc000021a {Fatal System Error}
	After you install Roxio GoBack (included with Norton System Works), and attempt to start your computer, you may receive an error message similar to the following: C000021a (fatal system error). The session manager initialization system process terminated unexpectedly with a status of 0xc000003a (0x00000000, 0x00000000) Your computer starts normally in Safe mode, but a clean boot from MSConfig has no effect.
	When you try to unlock your computer by pressing CTRL+ALT+DELETE, your computer restarts unexpectedly. You may receive the following Stop error: STOP: c000021a (Fatal System Error) The Windows Logon Process System process terminated unexpectedly with a status of 0xc0000005 (0x0000000 0x00000000).The system has been shut down.