Officially it is no longer possible to remote map the single bay/single drive My Cloud like one could do through the MyCloud.com web portal a few years ago. WD removed that feature.
Currently the only official ways to remotely access a single bay/single drive My Cloud is using the MyCloud.com web portal, the My Cloud Desktop software, the My Cloud mobile app for iOS/Android, or the insecure FTP.
If one has the older first gen v4.x single bay/single drive My Cloud it may be possible to hack, using SSH, the firmware using the following unofficial mod to regain the ability to remote map. This mod does not work on the second gen v2.x single bay My Cloud units.