Hard drive transfer

I'm almost positive you can if you have the hard drive space but not at the same time. Plug one of the hard drives in the hard drive bay. Then plug in your empty hard drive into the transfer cable then the transfer cable to one of the usb ports on your xbox.
Transfer the data and repeat for the other hard drive. That should transfer all the data onto one hard drive. Hope this helps!

hello

just formatted my hard drive and its still saying unformatted i think my hard drive is broken and needs replacing

if i buy a new hard drive or Xbox do i need a data transfer cable to transfer from hard drive to hard drive?

but at the moment there is nothing on my Xbox hard drive to transfer

The transfer cable would transfer data from hard drive to hard drive. But it's not possible to transfer anything between accounts.

Hello Dragoon,

Taken from support.microsoft.com/.../937279

Things to know before you transfer content

Warning

Before you use the Xbox 360 Hard Drive Transfer Kit, please read the user's guide included with the kit.

You can move all content from one Xbox 360 Hard Drive (referred to as the "source hard drive") to another Xbox 360 Hard Drive (referred to as the "destination hard drive"). The content from the source hard drive overwrites the content on the destination
hard drive.

Once the transfer is complete, the original content on the destination hard drive is replaced with all the content from the source hard drive and the content on the source hard drive is erased.

Movie rentals

Movies you have rented on the source hard drive will not be available after the transfer. Make sure to watch all Zune movie rentals before you use the Hard Drive Transfer Kit.

Using the Hard Drive Transfer Kit

Warning With any transfer, there is a slight risk that some or all of your content might be lost during the process. Microsoft is not liable for any loss of content that results from the transfer process.

Only one hard drive can be connected to your Xbox 360 console at a time. The transfer cable cannot be used to connect multiple hard drives to your console at the same time.

When you transferred the content over to the new hard drive, did you have the old or new hard drive plugged into the transfer cable?

If you had the 120GB hard drive plugged into the transfer cable that may be where the issue is being caused, would you be able to transfer the data back to the 20GB hard drive, plug the 120GB hard drive into your console, format it then try transferring
the data back to the 120GB hard drive with the 20GB hard drive plugged into the transfer cable and the 120GB hard drive plugged into the console.

Scroll down and follow the "Format a storage device":
support.xbox.com/.../storage

Let us know how it goes!