Getting Error while sending mail form outlook
The connection to the server has failed. Account: 'customer-domain.com', Server: '18.104.22.168', Protocol: SMTP, Port: 25, Secure(SSL): No, Socket Error: 10060, Error Number: 0x800CCC0E
This is because the customer not able to connect to port 25 of mail server.
- Server May be Down
- Mail Server May be Down
- Firewall Blocking Port 25
To Verify SMTP server working, run
telnet domain.com 25
If connected SMTP server is working.
Since windows firewall do not Block IP by itself, mostly, it can be server down or customer internet problem.