UK here.
I downloaded a free update using automatic update. Is this the same? It was free too.
Let Us know.
Before purchasing the 802.11n Enabler software, please check to make sure that your Mac does not already have the 802.11n enabler already installed.
* Open Network Utility (found in the Applications > Utilities folder)
* Under the Info Tab, choose Network Interface (en1)
* In the section "Model: Wireless Network Adapter," if it says (802.11a/b/g/n), you already have the 802.11n enabler installed. If it says (802.11a/b/g), you do not have the 802.11n enabler installed.