May be causing problem with a driver at shut down

[Paul44070]

It seems to be related strictly to the Norton backup software and disconnecting of the USB drive.
I set Policies for the drive to "Optimize for quick removal" and then disconnected the drive, although I went into Suspend mode first just to be sure that nothing was being written to the drive. No "Safely Disconnect" of the drive is supposed to be needed, since writes are not being cached.

After the USB drive light blinked a couple of times, and then went out, I disconnected the drive; woke up the computer, and then did a shutdown: the same driver (symsnap.sys) was than blamed for a BSOD that I got.

Only one of my previous BSOD's occurred following the use of that particular drive.
I always log the backups, so I know how long it has been since the last time I used that drive.
But this problem could also have been caused by my use of a much smaller portable USB hard drive, that I often update for use when traveling. That drive would safely disconnect at times, and would not at other times. So I set it to Optimize for Quick Removal, and just disconnect it after the updates.

I don't keep track of the dates when I update the travel drive, so I could easily have used it used it prior to the BSOD's that occurred. Since I try not to do actual Windows shutdowns, but use Suspend Mode instead, I wouldn't recognize that using that drive was the cause of a BSOD that resulted days later.
That's my latest theory, anyway.

I think we can exonerate CleanMem.
Having a debug report that seemed to indicate an attempt to access freed memory was what started me along this path.
Consider your track record of no problems to be intact.
Thanks for following along with me on this.
Paul 

[Shane]

Good to hear

Let me know how it goes when you try the different drives and see if it is related to the one drive

I forget, did you check the usb drive for any bad sectors?

Shane

[Paul44070]

I forget, did you check the usb drive for any bad sectors?

I didn't mention it, but I had Windows check the drive for errors: OK