Thanks for the link.
Tried several of the debug options, which all seem to work, but there's no details that seem out of the ordinary in the log, and nothing I can pin down as being suspicious on the drive.
The drive is in a USB caddy for all of this, so not active as a system or boot drive.
I have tried running a full checkdsk, which worked OK.
I then tried a full defrag, which again pulled the same crash
I then tried an error check in defraggler, which ran to conclusion OK
Another attempt at a defrag pulled a crash again.
Then tried a file defrag, which ran OK, and at the end, there was 0 files fragmented.
Full defrag still pulls error crash
Tried using CCleaner to do a wipe free space, which ran OK
Tried Defrag again, still crashing.
Not sure what to try, or what to do with this at the moment, it's the only machine of a number I am involved with that's pulling a crash. If I defrag the system drive on this machine, it's fine and runs with no hassle, so my suspect is that there is a pattern in a file or index that is somehow confusing defraggler, but there's no indication of anything abnormal in the debug log, even at level 3.
Not even sure any more if there is a problem as such, other than I can't run full defrag on this drive.