Indesit Aquarius DWF 40 Not Emptying?

I have cleaned the filter, topped up the salt and rinse aid, yet I still get a problem ... the machine simply stops mid-wash-cycle with two flashing green lights (Prewash and Wash). After I manually drain the bottom of the dishwasher... either by syphoning the excess liquid out or by sucking on the extraction hose and draining the fluid that way (not pleasant!) The machine is then able to start. It then starts a wash cycle but fails between 5 and 10 mins after the cycle has started. Any thoughts / ideas?