Windows applications do not launch from the Mac side ( e.g. from Dock, Windows Applications folder or Launchpad) or files associated with Windows application cannot be opened from the Mac side (from Finder)
/etc/hosts file on the Mac side has been changed by an accident.
Open Terminal (Applications -> Utilities -> Terminal) and type in following command:
less /etc/hosts |grep 127.0.0.1.*localhost
If command will not get any output then input following command:
echo “127.0.0.1 localhost” | sudo tee –a /etc/hosts
and press Enter. Your Mac user account password will be required. Note that you will not see characters appearing, so just type it in and press Return/Enter.