Hi. I am running Paragon Backup & Recovery™, version 10, build 9105 (18.11.09 ) Free Edition in Windows 7 64 bit. I backup to a USB external HD. It has worked fine (both to backup and restore) till today. When I tried to backup today, it could not finish the backup. The log says: "Backup [virtual] succeeded" but "Backup [committed] failed VSS: Can't read volume data" Not sure what VSS is. I checked the external hard drive and it was fine. What should I do? Thanks.