Unable to select Continuous Backup option

I would like to configure Smartware to continuously backup a folder on my hard drive to my Dropbox account, but when I go to the “Set Backup Frequency” window, the radio button for “Continuous Backup” is grayed out.  Any idea why this might be happening?


According to the WD Smartware user’s manual page #42

“The initial/default configuration of the WD SmartWare software is for continuous backups.”