If you cannot reach your My Cloud (on a Mac) via the My Cloud name (typically “mycloud”) via a web browser. There are a couple of ways to find the IP address used by the My Cloud. One way is to download the WD Access for Mac which should discover the My Cloud on your local network (and I assume show the IP address for the device). The WD My Cloud Setup for Mac may also be able to find the IP address of the My Cloud on your local network. If the WD My Cloud Desktop for Mac is anything like the PC version it too should discover and show the IP address of the My Cloud on your local network. A second way is to check your router’s administration page and see what IP address it is handing out to DHCP clients including the My Cloud. Another way is to download a free network scanning programs from the internet that will scan your local network and display the various devices and their IP addresses.
Once you have the IP address in hand, use that in your web browser to access the WD My Cloud Dashboard UI.
Once you gain access to the Dashboard you can configure the My Cloud for a Static IP address. See either the My Cloud User Manual or the following WD SUpport document for how to set a static IP address: How to configure a My Cloud or My Cloud EX4 drive with a Static IP
Note: there is a big El Capitan thread discussing the various issues with El Capitan and the My Cloud.
