I tried to activate license of my system online but I recveived an error message(s): "Could not communicate with server.", "Activation failed. Error Code 2". What has happened and how can I resolve this issue?

This error means that communication port - port 80 (HTTP) - that activation module is using to communicate to your PC is not allowed in your company network. Ask your network administrator to temporarily open this port or use Manual Activation option.
You may also try temporarily disabling any firewall or Internet security software.