Lua

Verify Connectivity to the SMTP Server

Demonstrates the Chilkat MailMan.VerifySmtpConnection method, which tests whether a TCP/IP connection can be established with the configured SMTP server. It verifies connectivity only — it does not authenticate. This example configures the SMTP host and checks whether it can be reached.

Background: When a send fails, it helps to know where it broke. VerifySmtpConnection isolates the first hop — can the client even reach the server on the configured host and port, and complete the TLS handshake? A failure here points at networking, firewall, DNS, port, or certificate issues rather than credentials. Once connectivity is confirmed, VerifySmtpLogin tests the authentication step.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the MailMan.VerifySmtpConnection method, which tests whether a TCP/IP
-- connection can be established with the configured SMTP server.  It verifies connectivity
-- only (it does not authenticate).

local mailman = chilkat.MailMan.new()

-- Configure the SMTP server connection.
mailman.smtp_host = "smtp.example.com"
mailman.smtp_port = 465
mailman.smtp_ssl = true

-- Test connectivity to the SMTP server.
local connected = mailman:verify_smtp_connection()

if connected then
    print("Successfully connected to the SMTP server.")
else
    print("Could not connect to the SMTP server.")
end