CustomerAuthenticate Error

Error Message

Response not of type text/xml
request

POST /vtigercrm/vtigerservice.php?service=customerportal HTTP/1.0
User-Agent: NuSOAP/0.6.7 (1.1)
Host: gtt-blackhole.de
Content-Type: text/xml; charset=UTF-8
SOAPAction: "https://gtt-blackhole.de/vtigercrm"
Content-Length: 676

<?xml version="1.0" encoding="UTF-8"?><SOAP-ENV:Envelope SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:si="http://soapinterop.org/xsd"><SOAP-ENV:Body><ns1:authenticate_user xmlns:ns1="https://gtt-blackhole.de/vtigercrm"><user_name xsi:type="xsd:string">user</user_name><user_password xsi:type="xsd:string">pass</user_password><version xsi:type="xsd:string">5.3.1</version></ns1:authenticate_user></SOAP-ENV:Body></SOAP-ENV:Envelope>
response

HTTP/1.1 401 Authorization Required
Date: Wed, 09 Jul 2014 15:39:04 GMT
Server: Apache/2.2.22 (Ubuntu)
WWW-Authenticate: Basic realm="GTT Intranet Services"
Vary: Accept-Encoding
Content-Length: 484
Content-Type: text/html; charset=iso-8859-1

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>401 Authorization Required</title>
</head><body>
<h1>Authorization Required</h1>
<p>This server could not verify that you
are authorized to access the document
requested.  Either you supplied the wrong
credentials (e.g., bad password), or your
browser doesn't understand how to supply
the credentials required.</p>
<hr>
<address>Apache/2.2.22 (Ubuntu) Server at gtt-blackhole.de Port 443</address>
</body></html>
debug

soapclient2: call: authenticate_user, Array, https://gtt-blackhole.de/vtigercrm, https://gtt-blackhole.de/vtigercrm, , rpc, encoded; endpointType:
soapclient2: serializing param array for operation authenticate_user
soapclient2: in serialize_val: user, user_name, , , , , encoded
soapclient2: in serialize_val: pass, user_password, , , , , encoded
soapclient2: in serialize_val: 5.3.1, version, , , , , encoded
soapclient2: wrapping RPC request with encoded method element
soapclient2: endpoint: https://gtt-blackhole.de/vtigercrm/vtigerservice.php?service=customerportal, soapAction: https://gtt-blackhole.de/vtigercrm, namespace: https://gtt-blackhole.de/vtigercrm, style: rpc, use: encoded
soapclient2: SOAP message length: 676 contents: <?xml version="1.0" encoding="UTF-8"?><SOAP-ENV:Envelope SOAP-ENV:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/" xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:si="http://soapinterop.org/xsd"><SOAP-ENV:Body><ns1:authenticate_user xmlns:ns1="https://gtt-blackhole.de/vtigercrm"><user_name xsi:type="xsd:string">user</user_name><user_password xsi:type="xsd:string">pass</user_password><version xsi:type="xsd:string">5.3.1</version></ns1:authenticate_user></SOAP-ENV:Body></SOAP-ENV:Envelope>
soapclient2: transporting via HTTP
soapclient2: sending message, length: 676
soapclient2: transport debug data...
soap_transport_http: scheme = https
soap_transport_http: host = gtt-blackhole.de
soap_transport_http: path = /vtigercrm/vtigerservice.php
soap_transport_http: query = service=customerportal
soap_transport_http: entered send() with data of length: 676
soap_transport_http: connect connection_timeout 0, response_timeout 30, scheme https, host gtt-blackhole.de, port 443
soap_transport_http: connect using https
soap_transport_http: cURL connection set up
soap_transport_http: set cURL payload
soap_transport_http: send and receive with cURL
soap_transport_http: No cURL error, closing cURL
soap_transport_http: found proper separation of headers and document
soap_transport_http: cleaned data, stringlen: 484
soap_transport_http: end of send()

soapclient2: got response, length: 484 type: text/html; charset=iso-8859-1
soapclient2: Entering parseResponse() for data of length 484 and type text/html; charset=iso-8859-1
soapclient2: Error: Response not of type text/xml