- Plesk for Linux
Unable to receive/send e-mails.
It is not possible to connect to the server by telnet on port 25:
# telnet <server_ip> 25
telnet: connect to address 192.0.2.2: Connection refused
SMTP Port 25 is blocked by firewall.
If the firewall is configured in Plesk, open 25 port on the server in Tools & Settings-> Firewall
If the firewall is not configured on the server, contact your hosting provider.