BackupAssist imaging jobs utilize the Microsoft Windows imaging engine to backup and write your data.
As some of you may already be aware, there is a known Microsoft issue when using the Windows imaging engine to back up to a destination drive that is utilizing 4K bytes per cluster. This typically relates to the larger (>2TB) USB hard drives that are now becoming more common. Some hard drives can be reformatted using 512 bytes per cluster rather than 4K bytes per cluster but unfortunately not all have this option.
Microsoft has addressed the issue within a new version of the Windows imaging engine found in Windows Server 2012 and Windows 8. Unfortunately though, for the Server 2008 and Windows 7 platforms, you still cannot use destination drives formatted with 4K clusters.
For this reason we recommend that you refer to this Microsoft compiled list of tested drives when choosing a USB drive make and model to backup image data to.
(please note this is an external list of user tested drives so no guarantees can be given)