Sending of the message failed. The message could not be sent because connecting to Outgoing server
Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) mail.cp.co.id failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again.
Sending of the message failed.
The message could not be sent because connecting to Outgoing server (SMTP) mail.cp.co.id failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again.
Alle svar (1)
So have you verified your settings are correct and you do not have a firewall (usually software) blocking internet access for Thunderbird?