Unfortunately with the My Cloud Desktop app for Windows/Mac being End of Life in 2016 and no longer functioning with the single bay/single drive My Cloud units in the last year or so that run recent versions of the firmware, the only official methods of remote access to the single bay/single drive My Cloud units are the MyCloud.com web portal, the WD My Cloud app for iOS and Android, or the insecure FTP option.
The MyCloud.com web portal and the corresponding My Cloud Dashboard Remote Access/Cloud Access option is what it is. A hiccup or outage in either one and one typically looses remote access. This is made worse by local broadband providers who block or filter the default ports used by the My Cloud for remote access. When this happens a user is forced to reconfigure their My Cloud Dashboard > Settings cloud access/remote access setting to manual and set alternate external ports. Then one would need to configure, within their router, port forwarding for those external ports to the My Cloud.
Or one can bypass WD all together and setup their own VPN server on the same local network as the My Cloud. Then using a VPN client on the remote device/computer one can VPN tunnel into their network containing the My Cloud securely, and access the My Cloud as if they were on the same local network. However this VPN option usually requires more computer knowledge and experience to properly configure the VPN server/client for remote access and security. Some consumer routers (Asus for example) include several VPN server options including the popular OpenVPN server.