Activation diagnostics.
Activation codes belong to installs from before 4.9; the current download needs none. If an earlier install would not activate on your PC, run these two checks. They narrow the problem down to the server, your network, or the code itself — and tell you exactly what to send me if it is still stuck.
Is the activation server reachable?
This asks the activation server whether it is running, from your browser on this network.
Does the server recognise your code?
Enter the code you were sent. The server answers only whether it exists; it is not activated, claimed or used up by this check.
What each outcome means
Server reachable, code recognised
The server, your network and your code are all fine. The failure is happening at the moment the app claims the code for your computer. The most likely causes are that the code was already activated on another computer, or that something on this PC is interfering with the app's connection. Email me the exact wording shown in the app and I will check the code's status at my end.
Server reachable, code not recognised
The code did not match anything in the database. Check it character by character against your purchase email, watching for a missing character or a letter typed in place of a digit. If it still fails, reply to your purchase email and I will confirm the right code.
Server not reachable
Your browser could not reach the activation server at all. Try again on a different network, such as a phone hotspot, and turn off any VPN. If a hotspot works and your usual network does not, the network is blocking it. If the app fails but this page works, suspect antivirus or firewall software inspecting the app's connection specifically.
Both checks pass but the app still fails
This is the most useful result to report, and it does not mean your code is bad. These checks run in your browser; the app makes its own request, and the two can be treated differently both by security software on your PC and by the protection sitting in front of the server. A request can be refused before it ever reaches the activation server, and the app then has nothing specific to show you — which is why it falls back to wording as vague as “Activation failed. Please try again.”
If you see exactly that wording, email me: it identifies the problem precisely, and there is a fixed installer for it. Please do not keep retrying, as it will not clear on its own.