My i5 256GB is has 71GB use on the C drive. I want to back up my data (not image) to a NAS drive I have. When using the default incremental scheme the resulting back up is 205GB or pretty much three times the used space. Then a subsequent incremental is another 180GB. So after two backups 385GB is used on my NAS, to backup the 71GB of space used on my SP3! Why is acronis seemingly backing up the free space on my 256GB C drive? Is it because the SP3 hdd is encrypted?