Just thought I would let people know if they come across this blog and attempt this upgrade. It is not for the faint hearted. You have been warned! The act of opening the case puts strain on the ribbon cables that connect the touchpad and keyboard at the keyboard end. This is why the poblem is not immediately apparent from the inside. If you are unlucky, and I was, they will pull apart from the very flimsy connectors. If your keyboard or touchpad stops working the thing to do is lift the keboard off carefully. There is no need to even have the laptop case open to do this as it just lifts upwards after holding back some plastic clips at the back with a very small screwdriver. Underneath the keyboard you will immediately see the connectors that have been pulled out. One or the other may still be attached hence the be careful warning. It is tricky to get them back but a bit of patience and your panic will be over.