致命错误：未捕获的SoapFault异常：[WSDL] SOAP错误：解析WSDL：无法从中加载....无法加载外部实体

Question

我想从SOAP服务获得响应。而且我总是收到错误致命错误：未捕获的SoapFault异常：[WSDL] SOAP错误：解析WSDL：无法从中加载....无法加载外部实体。 我尝试以下脚本：

$wsdl='http://xx.xx.xx.xx:xxxx/xx/xxxx?wsdl';
$soapclient = new SoapClient($wsdl, array(
    'login' => "xxx",
    'password' => "xxxx",
    'encoding' => 'UTF-8', 
    'verifypeer' => false, 
    'verifyhost' => false, 
    'soap_version' => SOAP_1_1, 
    'trace' => 1, 
    'exceptions' => 1, 
    "connection_timeout" => 180, 
    'cache_wsdl' => WSDL_CACHE_NONE
));
$param=array('studentNumber'=>'0001');
$response = $soapclient->getStudentInfo($param);
var_dump($response);

任何人都有解决方案，请帮助我，我对此错误感到困惑。我需要帮助。