The initial release of NovaBACKUP version 16.5 "R1" will always display warnings in backup logs related to read-only or system/protected files that cannot have the archive flag (archive bit) reset by NovaBACKUP software. The log warning in these cases will read "Unable to reset archive flag for read-only file..." For instance, if the Windows System32 folder is part of your selected file backup set that folder contains many Windows system protected files and will display a warning in our logs if either the Full, Differential or Incremental backup modes are utilized. You will also see these warnings in this version if the files selected for backup are on a network location which is a non-Windows based file system (the main example Windows based file system would be NTFS). An example of this would be a NAS or SAN file system which is typically a Linux based file system (a non-Windows based file system). If files located on a NAS or SAN are part of your selected backup selection for a backup job and you are running version v16.5.1106 then you WILL see these warnings in the job logs. The backups which contain these warnings will still be completed backups. The updated version 16.5 "R2" 16.5.1215 has now been released December 18th 2014 which corrects the warnings for "unable to reset archive flag".
NOTE: Only the "SnapShot" backup mode will not show these warnings since that method does not attempt to call or reset the archive flag/bit. Full, Differential and Incremental backup modes will be affected by this type of log warning until the aforementioned new release is released and installed which will be 16.5 "R2" 2 which has a build number of 16.5.1215. The downloads page has the current version posted and the update notice should be triggered to show this version is released.
An example version 16.5 backup log entry will look like this if it encounters system protected or read-only files in the selected backup set: