Online Backup only supports drives that Windows recognizes as “fixed.” Online Backup does not support “unfixed” or removable drives such as thumb-, or flash, or external drives. If you want to back up data from a removable drive, first copy the data onto one of your fixed drives, and then select the data for back up.
IMPORTANT NOTE: If you have selected files from an external drive to be part of your regular backup and you unplug or turn off the drive while your computer is running, Online Backup will detect that the files are gone and will assume that you no longer need them. Those files will then be marked for deletion. After 30 days, the files will be deleted from our servers and you will not be able to get them back.