This relatively obscure fix worked for me after long hours of research. Has to to with the elected “master browser” for your network workgroup in Windows. WDTV being legacy depends on this support for shares and has trouble if it is set to anything but your router (due in part to other machines being less dependably available on network). Here’s how to remedy:
Explanation of master browser function and invaluable “lanscan” tool to determine current master browser:
From the above linked page download the lanscan zipped .exe (green “Download” link about 1/3 down the page), put the .exe in your windows folder and run the command “lanscan” from an admin command line window. This will list all the participants in your workgroup. If you do not see your router listed as “MASTER” you need to change settings in the Windows registry of the machine(s) listed as master browser. Here’s how:
https://pattersonsupport.custhelp.com/app/answers/detail/a_id/8124/~/disable-the-master-browser
FYI Windows 10 deprecated the master browser functionality for a time and then reinstated it. Check your the version of any Win 10 boxes you’re operating on to make sure that have a version that includes master browser functionality:
https://social.technet.microsoft.com/Forums/en-US/3101aeef-115f-4b6e-94c1-c3d0f575b116/master-browser-restored-to-windows-10?forum=win10itpronetworking
Another WD community thread discussing this material: