Difficulty activating eLicense

Hi all,

I have purchased and downloaded Cubase 8 but am having difficulty activating the eLicense. When I enter my activation code the ‘Cubase 8 upgrade from Cubase 7.5’ label is displayed correctly, I press continue, then a screen comes up called ‘Select License to Upgrade’ but no Licenses are displayed only the eLicencers in the left column (‘Upgradable licenses’ and ‘Soft eLicenser (SeL)’ which has a cross through it/not available.
There is also a statement at the bottom of the screen saying:
‘Currently, there is no license available which can be upgraded by your upgrade license. Please connect an USB-eLicenser, which holds an appropriate upgradable license, to your computer.’
I have got the ‘Cubase 8’ USB and the ‘eLicenser Control’ USB connected.

Is there another USB I need to connect perhaps?
Any help/suggestions would be great.