Troubleshooting: Unable to Send Email (SMTP Errors)

If you are unable to send email, please check the specific error message you are receiving. Most issues are caused by either ISP port blocking or incorrect client authentication settings.

Scenario 1: "Server not found" or Connection Timeout

Symptoms: The email client tries to connect for a long time and then times out, or immediately says the server cannot be found.

Cause: Many Internet Service Providers (ISPs) block TCP Port 25 to prevent their users from sending spam. Since most email clients default to port 25, this prevents legitimate connections to our servers.

Solution: Change your Outgoing (SMTP) port.

• Open your email client settings (Outlook, Thunderbird, Phone).
• Locate the Outgoing Server (SMTP) settings.
• Change the port number from 25 to 26.
• Save and try again. We have port 26 open specifically for this scenario.

Scenario 2: Error (550) No Relay / (530) Authentication Required

Symptoms: You connect to the server immediately, but when you try to send, you get a "550 Access Denied," "Relaying Denied," or "530 Authentication Required" error.

Cause 1: Missing Authentication (Most Common)
Our servers require you to log in before sending mail. You cannot send mail anonymously.

Solution:

• Open your email client's Outgoing Server settings.
• Find the checkbox labeled "My outgoing server requires authentication" (or "Use same settings as my incoming server").
• Ensure this box is CHECKED.
• Ensure you are logging in with your full email address (e.g., user@example.com), not just the username.

Cause 2: Router/Firewall Interference (Advanced)
In rare cases, aggressive corporate firewalls or older routers (specifically Cisco devices) may strip authentication headers from your connection.

Solution: Contact your network administrator. If you are using a Cisco router with "Deep Packet Inspection" enabled, try removing the command ip inspect smtp to allow standard authentication protocols to pass through.