Instructions
Turn the Xbox 360 off. Attach all of the hard drive based devices to the Xbox 360.
Turn the Xbox 360 on. Select the "My Xbox" tab. Select "System Settings." Select "Memory."
Choose the hard drive with the original file you want to copy to another hard drive. Select the type of content (e.g Videos) that you want to copy.
Select the file that you want to copy to another hard drive. Select "Copy." Select the hard drive that you want to copy the file to. Repeat steps three and four until you&'ve transfered all of the files you want.