I'm using Paragon v11 for a client who is using two hard drives to backup server data. Each week we swap drives on Friday mornings for a full backup over the weekend. Then Monday through Thursday we run differential backups on the same drive. On the next Friday we swap drives and the cycle starts again. This is done to keep one drive offsite for disaster recovery. Looking at weekly backup logs I see successful backups for each nights differentials. Yet multiple times now when I need to restore data I find that Paragon cannot go back to differential backups to restore individual files. Usually the error is a 0x10023 error - but other times it references "Increment is not possible.". My question: How can we trust the backups when my logs show successful completions of backups each night? I have multiple backup sources (Paragon, Carbonite offsite, and shadow copies) and on more than one occasion - I can't get a successful restore from any of the three sources because of anomalies.