E4 error code means water has leaked into the base of the dishwasher.
What you need to do is pull the dishwasher out and tip it 45 degs backwards and this will allow the water in the base to drain out from the back. So you may need a towel for this part.
Once the water is out the anti flood switch in the base will reset itself and should take the E4 error code off.
Then retry it and see how it goes from there. If it happens again then there is a water leak in there so you need to remove the side panels and check the hoses under there and see if you can locate were the water is leaking from.
So try that and see how it goes from there but the E4 error code is a water leak in the base.
If you need anymore info just get back to me.