我试图使用PHP代码调用POST请求，但收到了401个未

$username = 'MyDomain	estuser';
$password = '123456';
$url = 'http://10.20.30.40:8080/TargetPage.aspx';

$data = array(
         'username' => $username,
         'password' => $password, 
         'postdata' => 'InputParameter1=Test1&InputParameter2=Test2'
);

$options = array(    
    'http' => array
            (
                'method'  => 'POST',
                'header'  => "Content-type: application/x-www-form-urlencoded
",
                'content' => http_build_query($data)   
            )           
);

$context  = stream_context_create($options);    
$result = file_get_contents($url, false, $context);

$options = array(
    'http' => array(
        'header' => 'Authorization: Basic ' . base64_encode("$username:$password")
    )
);