I have loaded an assembly but it has opened as if it is in modelling, with none of the add component tools etc, usually seen in the assembly window, available. Can anyone help solve this?
Sounds like the assemblies application is not on. Try under File (start) click and switch on Assemblies . Alternatively in the Applications tab click the assemblies button.
You may also need to right mouse click at the end of the ribbon bar and switch on the Assemblies tab.