- Plesk for Windows
- MailEnable mail server is used on Plesk server;
- Unable to send email from the server to external recipients using Outlook or other mail clients, below bounce email is received:
CONFIG_TEXT: 503 This mail server requires authentication when attempting to send to a non-local e-mail address. Please check your mail client settings or contact your administrator to verify that the domain or address is defined for this server.
- Allow relay for authenticated senders option is disabled in MailEnable > Servers > SMTP > SMTP Properties > Relay
Disabled Allow relay for authenticated senders option doesn't allow to send emails to non-local recipients.
- Log in to the server via RDP;
- Go to MailEnable > Servers > SMTP > SMTP Properties > Relay and tick Allow relay for authenticated senders option.
- Open Privileged IPs.. and make sure that
127.0.0.1is allowed for relaying.
- Restart SMTP service: MailEnable > Servers > SMTP > stop/start