Hello, Thank you for the feedback. Indeed, by enabling the option "Store backup as multiple data blocks instead of a whole VHD file," the backup is now in progress. However, given the low-end NAS being used, it will take a long time, as the process is saturating its CPU. Thanks!

@MrQ said: @jr-m4 thank you so much for testing this updated driver. Just to make sure, I understand now that you confirm the driver is working as expected and the issues you had were not related to it? Or are there any problems still with this new driver? Many thanks again for spending the time to test and report. Hi Yes. I believe I was chasing a red herring of my own doing. I have not found anything actually problematic with this driver at all.