This key works well on 3G but not EDGE. Nor with the TP-Link 3420 or with Windows 7! After contact with the TP-Link support, I got an answer that the version 2 firmware does not support EDGE (but as we can not downgrade this does not solve the problem) or need to buy a Another TP-Link router (Models 3020 or 3040). In short, the media did not solve my problem, but rather I explained how without. Fortunately, I used a old key ICON 225 which strangely works very well on EDGE and 3G on the TP-Link 3420.