check config_inc.php
<?php
$g_hostname = 'localhost';
$g_db_type = 'mysql';
$g_database_name = 'mantis';
$g_db_username = 'root';
$g_db_password = 'admin';
?>

check config_defaults_inc.php

• Hosts will be tried in order.
  • @global string $g_smtp_host
    */
    $g_smtp_host = 'mail.***';
    /**
  • These options allow you to use SMTP Authentication when you use a remote
  • SMTP host with phpMailer. If smtp_username is not '' then the username
  • and password will be used when logging in to the SMTP server.
  • @global string $g_smtp_username
    */
    $g_smtp_username = 'wlhsia@*****';
    /**
  • SMTP Server Authentication password
  • @global string $g_smtp_password
    */
    $g_smtp_password = '****';
    /**
  • This control the connection mode to SMTP server. Can be 'ssl' or 'tls'
  • @global string $g_smtp_connection_mode
    */
    $g_smtp_connection_mode = 'tls';
    // $g_smtp_connection_mode = 'ssl';
    /**
  • The smtp port to use. The typical SMTP ports are 25 and 587. The port to use
  • will depend on the SMTP server configuration and hence others may be used.
  • @global int $g_smtp_port
    */
    //$g_smtp_port = 25;
    $g_smtp_port = 587;

check config_inc.php.sample

• Hosts will be tried in order.
  • @global string $g_smtp_host
    */
    $g_smtp_host = 'mail.*****';
    /**
  • These options allow you to use SMTP Authentication when you use a remote
  • SMTP host with phpMailer. If smtp_username is not '' then the username
  • and password will be used when logging in to the SMTP server.
  • @global string $g_smtp_username
    */
    $g_smtp_username = 'wlhsia@**';
    /**
  • SMTP Server Authentication password
  • @global string $g_smtp_password
    */
    $g_smtp_password = '****';
    /**
  • This control the connection mode to SMTP server. Can be 'ssl' or 'tls'
  • @global string $g_smtp_connection_mode
    */
    $g_smtp_connection_mode = 'tls';
    // $g_smtp_connection_mode = 'ssl';
    /**
  • The smtp port to use. The typical SMTP ports are 25 and 587. The port to use
  • will depend on the SMTP server configuration and hence others may be used.
  • @global int $g_smtp_port
    */
    //$g_smtp_port = 25;
    $g_smtp_port = 587;
    /**

so,mantis didn't work,What can I do some？？？？