Suggestions

[Kevin]

The session might expire before your IP changes.

[KuJoe]

True but that's why it should take advantage of both checks. I just think that when you disable "Multiple signups" it should automatically include users who are logged in.

Code:

if($db->config("general") == 0) {
    $maincontent = $main->table("Signups Closed", $db->config("message"));
}
elseif(!$main->checkIP($ip) && !$db->config("multiple")) {
    $maincontent = $main->table("IP Already Exists!", "One account per user.");
}
elseif($_SESSION['clogged']) {
    $maincontent = $main->table("Already logged in.", "One account per user.");
}
else {
    $_SESSION['orderform'] = true;    
}

Short of checking cookies and IPs there isn't much more you can do but these are usually good enough.

---

To add user IPs to the client list in the admin control panel:

Add to end of includes\tpl\clientdetails.tpl

Code:

<div class="subborder">
    <div class="sub">
      <table width="100%" border="0" cellspacing="0" cellpadding="0">
        <tr>
          <td width="50%">Client IP:</td>
          <td align="right">%CLIENTIP%
          <a title="The IP used during registration." class="tooltip"><img src="<URL>themes/icons/information.png" /></a></td>
        </tr>
      </table>
    </div>
</div>

Find in admin\pages\users.php:

Code:

$array['EMAIL'] = $client['email'];

Add below:

Code:

$array['CLIENTIP'] = $client['ip'];

Repeat last step for second listing.