Carbon Copy Cloner users recently noticed a warning that ONE file, /private/var/db/fpsd/dvp, isn’t being backed up. Here’s why. (tl;dr. It’s not a problem.) This Apple discussion explains the situation for this user:
Carbon Copy Cloner gives me an error when I finish backing up, saying I can’t copy this file to my backup drive because it didn’t have permissions. What is it, and is it safe to use the backup without this file? When I go to the file in Finder, the folder it’s in doesn’t give me access.