I am working on a batch of files that I keep on an external USB. Everytime I finish a session, I use my mouse to select the files and copy them to another drive. I can always find my files when I return to the USB, but the backup won't save. I always check to make sure they are copied to the backup drive before closing. Everything looks OK, until I return and find a blank score in backups. Should I be using some other Save option?