After a clean installation process, firewall of Hyper-V Server is set to deny any remote connection by default.
If you need to management other than using console, you may want to enable inbound rules for Remote Management and Remote Desktop by running these commands in the console.
To enable the Remote Management:
cscript C:\windows\system32\scregedit.wsf /im 1
To enable the Remote Desktop:
cscript C:\windows\system32\scregedit.wsf /ar 0
And, you need to enable the remote desktop from the sconfig (the blue console window) also.