- Plesk for Linux
Unable to send email from Outlook or Thunderbird from a certain location:
Send test email message: Outlook cannot connect to your outgoing (SMTP) email server. If you continue to receive this message, contact your server administrator or internet service provider (ISP).
From other locations Outlook and Thunderbird are working fine. Email is working fine from the webmail from all computers.
25 port is blocked by the firewall or on an Internet Service provider side on the specific network
Allow connections to 25 port on the firewall on the server where issue is reproduced. If no firewall is blocking the connection to 25 port, contact Internet Service provider.