After setting up an Essential SE for your Mac, you will need to format the new drive. From tech support; Open applications folder, then open the Utilities folder, then open the Disk Utility, highlight the drive and click the partition button and select 1partition from the drop down. Then select the partition button lower right corner. After formatting, eject the drive and wait 10 secs. Plug-in and try that back-up. Do not update the firmware as some have suggested, it rendered my drive undetectable in that port.
Yep, as explained on the user manual, page 41 (46 if you seek the whole PDF)