To download a new WSDL, from the main menu,
1. Select Administration -> Web services.
In the left treeview, there will be link for 'WSDL download'.
2. Select the WSDL download link and it will prompt to save the wsdl zip file to a location on your local machine.
NOTE: You must be logged in as a user with web services permissions to access the Administration -> Web services link.