It was my RAM problem which is now solved but I just got this error two times and system was shutdown automatically but now its running fine.
What was the problem ?Code:This system is shutting down. Please save all work in progress and log off. any unsaved changes will be lost. This shutdown was initiated by NT Authority/system. MESSAGE the system process 'C:\windows\system32\lsass.exe' terminated unexpectedly with status code -1073741819 the system will now shutdown and restart.
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