Mode is set to users/devices. When we try to add a device, we get an error because $extDisplay is not set at the relevant place (it's empty, thus resulting in a broken query). Uninstalling the endpoint manager module solves the problem. Perhaps, you will just simply have to make it an "else if(!empty($extDisplay))" instead of an "else".
This is the relevant line of the error message:
SELECT mac_id,luid FROM endpointman_line_list WHERE ext = [nativecode=1064 ** You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 1]SQL -
Error occurs here (admin/modules/endpointman/functions.inc.php, line 154):
} else {
//Mac not set so delete
$sql = "SELECT mac_id,luid FROM endpointman_line_list WHERE ext = ". $extdisplay;
$macid = $endpoint->eda->sql($sql,'getRow',DB_FETCHMODE_ASSOC);
if($macid) {
//$endpoint->delete_line($macid['luid'], TRUE);
}
}