Sep 17, 2015 · For example, I have all my music files in one big, hierarchical directory on an external hard drive, backed up to a second external hard drive. ( FreeFileSync on my desktop PC keeps them in sync.) Nov 25, 2019 · For those who backup via iTunes/Finder, the journey isn't finished. Now it's time to backup iPhone to USB drive, an external hard drive that won't affect your storage on Mac. This should be done very carefully. Any attempt to extract files from the backup folder or using the wrong name of a hard drive may end up in a failure. Click "Finish" and then click "Yes" when prompted. Windows formats the new hard drive, partitions it and copies the system image from the external USB drive. After Windows finishes copying the system image to the new hard drive from the USB drive, the PC reboots automatically.