remove the top of the machine, 3 screws at the back.
slid off the top.
Look down inside and see the catch
In the middle of the black plastic part you will see a white bit of plastic protruding through a little.
This is the end of the door catch
using your finger push the catch towards the centre of the door and at the same time pulling the door release handle if it is still attached.
door should open.
bob.the.builder, August 2009