Fatal system error Stop c000021a Fatal System Error. This is a Windows stop error, (also referred to as âœThe Blue Screen of Deathâ or BSOD error or kernel error). The stop error message usually reads: STOP: c000021a {Fatal System Error} The Windows Logon Process system process terminated unexpectedly with a status of 0xc06d007e (0×00000000 0×00000000). The system has been shut down. What Causes Stop Error c000021a? A fatal system error, also known as a system crash, stop error, kernel error, or bug check, occurs when an operating system halts, because it has reached a condition where it can no longer operate safely. In Microsoft Windows, a fatal system error can be deliberately caused from a kernel-mode driver with either the KeBugCheck or KeBugCheckEx function. However, this should only be done as a last option when a critical driver is corrupted and is impossible to recover. This design parallels that in 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. This thread is locked. 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. fatal system error. I have an almost 6 year old Dell Dimension 8250 and have been having trouble all week with blue screens. However I was always able to get back into Windows. I have been running chkdsk and it found loads of problems with the hard disk. Strange because I run it every month and am diligent about computer housekeeping. I tried to defrag but it said to run chkdsk again and I did, but then I got the final blue screen which I cannot get past. STOP: c000021a {Fatal System Error} The Windows Logon Process system process terminated unexpectedly with a status of 0xc0000005 (0x00000000 0x00000000). The system has been shut down. I Trust that many of you have more computer experience than me so what would be the best thing for me to do now to fix this.. Sloppy mincing eyedropping biopsy. Stop c000021a {Fatal System Error} The session manager initialization system process terminated unexpectedly with a status of 0xc0000017 (0x00000000, 0x0000000) The system has been shut down. Solution. Download Available to Completely Repair the Stop C00002lA Fatal System Error. Recommended: Download the Automatic Repair Utility to correct this and other PC performance issues. Download. Certified safe, virus free download. Error Tools Editorâ™s Choice. Error Causes. and after that i got this error. safe mode is not work and last know good configration disnt have any effect. sugguest a way out of this....!!!!! choose the bit version for the system being scanned, not the system you make the disc on. http://windows.microsoft.com/en-US/windows/what-is-windows-defender-offline. After this see if it will boot into windows..