Cant create hyperv machine

Working with a non domain HyperV server and a windows10 workstation.
connecting to the server with the admin center is not a problem,

when i like to create/start/change a virtual machine ill get the error message :
(translating dutch to englisch) 
Cant get storagelocations, Error at line 49 char 232 +.. Remote Server Administration Tools | Managementtools for … Unexpected token "s" in expression or statement at line 49 char 232 +.. Remote Server Administration Tools | Managementtools for … the hash literal was incomplete at line 50 char 2 + function cvt$0 return convertfrom json unexpected token } in expression or statement what can we do to fix this? Henri