This error can appear if one of the files from the backup set is open at the time of backup. Ensure that any files that you back up are not in use and run the backup again. Before you run the backup again, exit all the programs and restart the computer.
This error can also occur if a backup is prematurely canceled before the completion. As a result, one of the files from the backup set is locked. To fix this problem, you need to wait for that file lock to be released which can take up to 24 hours. If the error persists, contact Norton support for further assistance.
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