Crash on defragment virtual disk (file mount as disk in Win10)

Windows 10

I have create a virtual disk (buitl-in disk managment in windows 10).

It is a file use as a disk mount in my case in %appdata%/roaming/firefox ( nothing special ! )

I mount it ...

The virtual drive work fine ...

I see that 'virtualdrive' drive in the list of the disk of defraggler

I analyse it => OK

I start defrag and it defrag it ...

BUT when the process 'look like finish' deffraggler crash.

Note: you probably have recived the 'crash dump'. i send it two time ...

Thanks for your product.

See you.