Thanks for your replies. But if I do not have permissions for that, then how is the file accessed and copied? There are no warnings in Karen's Replicator's log.
In any case, these are backups of files either to/from in the Shared Documents folder which my wife and I share for documents, photos, etc. and it is better to keep backups on each other's HDD. So permissions should not be a problem.
Wait a minute - could encryption be a problem here?