The Symantec Endpoint Protection (SEP) for Mac client is configured to not repair or quarantine detections. There are three places to configure this option in the Virus and Spyware policy under Mac Settings.
• Scheduled Scan configuration and Common Settings
• Administrator On-demand scans and Common Settings
Even if these features are set to not repair or quarantine files, the definition update scan may quarantine or delete files.
As a workaround, create SEP scan exceptions and/or submit files as False Positive if known good files are being deleted.