Twice , if you only want to make a backup of your other zip..you can format the new zip via the G1000, then using the external zip drive, save your G1000 zip with your data to a folder on your main hard drive.Be carfull not to edit anything, just copy to your C drive..
Second step is to copy the contents of the new folder[not the folder, only the saved contents], onto the new formatted zip..It will ask you if you want to overrite the sub folders..to this answer yes...After a few minutes the new zip can read in your G1000 or Zip 250 connected to the G1000 via SCSI...