The operating system of the Anycast is Linux & the drive format is fs3.
Format the USB drive & the hard-drive using Anycast internal file manager.
Unfortunately the only officially supported hard drives are the Maxtor One touch III. I believe they’ve just added another couple of drives & these are Maxtor too.
To see these files on a pc afterwards you’ll need to use a utility like Paragon Ext2FS Anywhere.
Hope this helps.