I have an HP pavilion laptop with a 500GB hard drive. I have about 270 GB of information in my internal drive. I hooked up a 5TB Seagate drive to make scheduled backups since December 2014 and now the drive says it is full. I know I have not saved 5TBs of information in my internal drive....... what am I doing wrong??? How can I clean up the external drive so I don't have duplicated files? and how do I prevent it from creating duplicate backups? I thought an external drive would only backup the drive by adding copies of the new files it found..... is that not the way it works??? will manually deleting the duplicated files ruin the back up entirely???