Continuing the discussion from Cannot access WD MyCLoud through File Explorer anymore:
I’ve studied a lot of solutions for this issue (most of them desperate), I’ve applied some of them (w/o results) and I’ve found the simplest one related to NAS.
So, briefly my situation: upgrade to w10 from w8.1, the same symptoms and messages as per c_criner, I see in navigation pane WDMYCLOUDEX2 (not mapped because is in cloud) and I can’t remove from Network because (normal!!) is not indicated as mapped.
The solution is to connect NAS through Dashboard and to proceed: Network Settings menu, Windows Services: Max SMB Protocol set to SMB1 ( Default SMB2 )- that fixed it for me (don’t ask me why, but I assume that something blocked my drive)