I would imagine it doesn't work because it's not designed to use floppy disks. One floppy can hold 1.2mb of data. You've asked to backup the complete hard disk to floppy. Let's assume you have around 20gb of data on the PC. That's the equivalent of around 900 floppy disks! A significant number of single files will be greater in size that one floppy disk. If you want to back up to external media you need to be thinking about rewritable DVDs or an external hard disk.
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Do you know that we're all in line for succession to the throne? Really?
Well, if forty-eight million, two hundred thousand, seven hundred and one people died I'd be Queen.