Answer:
its a host based firewall
Explanation:
because the administrator put it ntentionally and the only way do disable the firewall is by signing in as the admin (if you're the admin) and turn it off manualy
or if you're not the admin, ask them to do so.
Generally I'd recommend not buying one online, tends to be cheaper from a shop - and better used, although their are some risks with 2nd hand devices, I think the big price cut it worth it.
If you did want to buy online, maybe Amazon or Ebay?
For a simple answer, it is aproximately 7 times more than a CD.