Hi
In : moduls/auth_ldap/config_ldap.php
- you will finde :
$_ldap_config = array (
    // default configuration for all companies
    'default' => array (
        // LDAP authentication enabled?
        'enabled' => true,
        // LDAP configuration
        'ldap' => array (
            'host' => 'ldap',
            'port' => 389,
            'domain' => 'mycompany.com.au',
            'suffix' => 'dc=mycompany,dc=com,dc=au',
            'security' => 0,  // 0 = none, 1 = TLS, 2 = SSL
        ),
        // Map LDAP groups to FA roles
        // (first matching group sets the user's role)
        'group_role_map' => array (
            'Accounts Payable' => 'AP Officer',
            'Accounts Receivable' => 'AR Officer',
            'Sales' => 'Salesman',
            'Stores' => 'Purchase Officer',
            'Managers' => 'System Administrator',
            'Wheel' => 'System Administrator',
        ),
    ),
    // per-company overrides
    // (you can override 'enabled', 'ldap', or 'group_role_map' keys)
    'company' => array (
/*
        // example: this company doesn't use any LDAP authentication
        1 => array (
            'enabled' => false,
        ),
        // example: this company has some separate groups just for this company
        4 => array (
            'group_role_map' => array (
                'OtherCompany Accounts Payable' => 'AP Officer',
                'OtherCompany Accounts Receivable' => 'AR Officer',
                'OtherCompany Sales' => 'Salesman',
                'OtherCompany Stores' => 'Purchase Officer',
                'Managers' => 'System Administrator',
                'Wheel' => 'System Administrator',
            ),
        ),
*/
    ),    - AND this is what you have to set as "false"
// example: this company doesn't use any LDAP authentication
        1 => array (
            'enabled' => false,