Click the Apple Remote Desktop icon to activate the service, then select Access Privileges . :
Please check all the boxes in that window, and most importantly the VNC viewers section may control screen with password :
Quite simply, you have completed the basic steps. Now you can directly control Mac OS X with VNC Viewer on Windows with the previously set account. This way, you do not need to install some Mac applications like OSXvnc or cotvnc anymore. Good luck!