drainage problem on Bosch Classixx WFO2867b?

Hi hope someone may be able to help have just purchased a second hand Bosch machine. On trying it out discovered water all over the floor. On closer inspection i can see at back of machine when draining water is overflowing out of drainage tube? Why would this be ? Had an old neighbour look at it and hes taped the drainage hose to the drainage pipe. I know this will not work any advice please

bamblolo
October 2009