I've been having problems cloning large external usb drives, falling fowl of the limitations of windows archaic copy processes.
Once a month I backup my working 2tb WD elements drive to another 2tb WD elements drive.
Research showed that Windows has caching limits. So I tried Teracopy
but it failed with the same error (copying just stops and the drive access lights blink quickly and metronomically - no error message).
The I tried Driveimage XML
which has a clone disk function. This is working but it's now at 80% after FOUR DAYS.
Any recommendations for quicker free disk to disk copying utilities for Windows (7 and XP). I also need backup copy files from internal to external drives.