I am programming a driver in kernel mode. I need my driver to detect a BSOD. When BSOD occurs my driver will write a flag out a registry or a file to mark BSOD occurred .In next boot ,My driver will read this flag to know BSOD in previous boot. if the flag is set the driver do something. I found a way to detect BSOD by using KeRegisterBugCheckCallback routine. this routine registers a BugCheckCallback routine, which executes when the operating system issues a bug check. but I don't know how to write file of write Registry in this callback (In this callback , ZwWriteFile or ZwSetValueKey can't do that) Is there any way to do that? or is there any other way to detect BSOD in previous boot ? Thanks.