I got the same error message and when I tried to reinstall the firmware, my POD HD 500X stopped and shown " UPDATING FIRMWARE" , after I unplugged the power , and restart the POD, my device keep rebooting and shown the Line 6 Logo and the first patch page. In fact, I have also try to reset the device by holding down the left arrow button then plug the power adaptor, but same things happened. I am extremely disappointed. Anyone can help?