Synology 1817+ and Synology 918+ both core servers are running OK. They both can’t add a network path. The message always show unexpected error. \IP\folder name OR smb://IP/folder name. Same address was tested under MAC and Windows. Both OK. I even tried \IP or smb://IP both showed ‘invalid network path’, which is tested OK in MAC OS X and WINDOWS.
1817+ or 918+ locates at the same VLAN of network folder source. network should be no problem at all.