According to the official website, the software supports the following devices and partitions:
"Internal hard disks, external hard drives, solid-state drive (SSD), USB flash drives, thumb drives, CD/DVD, network share, network-attached storage (NAS), cloud drive desktop apps, Hardware RAID and virtual machine systems, etc."
And these are the supported partition systems:
"NTFS, FAT32, FAT16, EXT2, EXT3 and other file systems".
You have to make sure the drive that you attach to PC corresponds to these specifications.
Here is the official website in case you have any other issues: http://www.backup-utility.com/free-backup-software.html