Hello @Philippe_CHAUMONT
Norton 360 v24.10.9535
Is your Norton 360 v24 an update install or clean install?
Does Norton LiveUpdate run?
Does Norton QuickScan run?
Does Norton FullScan run?
Please run Norton Live Update + Restart (not Shut down) machine.
Please try Manage against your Norton pre-set auto backup
Please try Settings tab → Back up common file types only = Off (red)
Please review Excluded files → Manage
Please try Sync
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