What happens if you attempt to access the My Cloud, or map the My Cloud Share using the My Cloud’s IP address? Do you have the same problem?
In the following thread there is some discussion on SMB in Windows 10 when Microsoft borked the SMB2 a while back. May want to take a look and see if anything in there might help. There is a suggestion in that thread to configure the router as the “master browser” for SMB if the router supports such an option.
