I attempted to set this up for a workgroup of computers mainly using Windows 7 Professional. I simply want to use the My Cloud EX2 as an attached storage device for backup. An icon appears in Network showing the device. Clicking on the device brings up the dashboard configuration software in a browser (you need to log-in to this). However, it was not possible to access the storage on the device. After struggling and unable to find out how to do this on the internet, I called Western Digital tech support. Here is the procedure that turned out to be successful: (1) Determine IP address of My Cloud EX2 Ultra by bringing up cmd and entering "arp -a" (no quotes) (2) Among the dynamic assigned internet addresses that are displayed, look for the physical (MAC) address of the My Cloud EX2; write down the corresponding Internet Address (ip address) (3) Open Computer; in bar at top, click "Map network drive" (4) Enter the following in the window that pops up --> Drive: Z: Folder: \\ip address\Public (keep default check mark in "Reconnect at logon"). Note that "ip address" is of course the ip address that you wrote down. (5) Click Finish You should see Network Location of Z: in Computer. There will be 3 default directories: Shared Music, Shared Pictures, Shared Videos. Now it should be possible for you to copy files to and access files on the My Cloud EX2 Ultra. Tech support told me that public can utilize all the drive space. My unit has 2 hard drives, each 4 GB. I kept the default at RAID 1 so that the content would be mirrored on the 2 drives.
P.S. After I connected a Windows 10 computer to the network, the share folders on the My Cloud EX2 Ultra miraculously showed up on all computers, even the Windows 7 machines. Hmmm . . .