C++

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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C++

#include <CkMailMan.h>

void ChilkatSample(void)
    {
    //  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).

    CkMailMan mailman;

    //  Configure the SMTP server connection.
    mailman.put_SmtpHost("smtp.example.com");
    mailman.put_SmtpPort(465);
    mailman.put_SmtpSsl(true);

    //  Test connectivity to the SMTP server.
    bool connected = mailman.VerifySmtpConnection();

    if (connected == true) {
        std::cout << "Successfully connected to the SMTP server." << "\r\n";
    }
    else {
        std::cout << "Could not connect to the SMTP server." << "\r\n";
    }
    }