Azure FileSync Agent Access Denied 0x80c8028a

One of the dangers of giving end users 'full control' over files and folders is they may remove the NTFS permission for 'SYSTEM'. This will break Azure FileSync synchronization.

The Azure FileSync Agent runs under local system privileges, and relies on 'SYSTEM' having NTFS full control permissions to every single file & folder that you need to synchronize from that fileserver.

When you run the diagnostic script FileSyncErrorsReport.ps1 you will see the error code 0x80c80018 for 'Access Denied', as in the Azure FileSync Agent itself does not have permissions to the files and folders on the server.

To remedy this, add the SYSTEM NTFS permissions and ensure this is propagated to files & folders below