VagCom!!

Hello all. I'm hoping I've posted in the right section?
I've got hold of 409.1 and am having some trouble with it. Initially it always came up with 'no response from controller'. My limited computer skills only took me about an hour to get the first fix (Moved com ports) then I could read the engine fault codes. I then tried the engine 2 module and it comes up with the 'no response from controller' again!!
What's going on??
I've got a USB cable from Ebay.