[mothered]

"Unable to contact license server. Check your network connection or contact your system administrator for help."
Thefuck?

If you've added the IP entries (0.0.0.0) In the Hosts file, remove It and see If It can communicate with the server. If all goes well, add It again thereafter.

The above Is a non-routable IP address (similar to 127.0.0.1) and loops back to your local/Internal network, hence any attempts to communicate with the server (Incoming & outgoing) will fail.

The key is blacklisted lol.

Unable to contact license server.

Based on the above, there's no communication with the license server, so It's not possible to Identify whether It's blacklisted against their database.