Hi, We have just bought a DeLonghi Caffe Treviso. We are not able to get any coffee/liquid to drip out of the filter holder. The problem seems to occur when we are trying to preheat the machine, for instance you suggest attaching the filter holder to the appliance (without coffee) then wait for 'ok' light to turn on then press coffee delivery switch and let water exit, except no water exits. what is the problem?

Sounds like you need to prime the water pump. Remove the filter holder, open the steam knob and then press the coffee delivery switch. Wait for water to flow consistently from the steamer and then close the steam knob. Water should then be forced to flow through the goup head (coffee head). If you cannot get water to flow from steamer then the pump may have already been damaged or it may have been faulty from the start. If water will flow through steamer but not for the coffee, then the group head is blocked. Good luck hope this helps and remember that all machines should be primed like this before use.