Readonly unlock isn't dealt with when copying an existing file instead of downloading it

        # Check if the file is already on the HD
        pair = self._dao.get_valid_duplicate_file(doc_pair.remote_digest)
        if pair:
            import shutil
            file_out = self._get_temporary_file(file_path)
            shutil.copy(local_client._abspath(pair.local_path), file_out)
            return file_out