Isn't the fact that the webservice wants:
soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
and it gets:
<v:Envelope xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns:d="http://www.w3.org/2001/XMLSchema" xmlns:c="http://schemas.xmlsoap.org/soap/encoding/" xmlns:v="http://schemas.xmlsoap.org/soap/envelope/">
<v:Header />
Same at:
<checkBarcode xmlns="http://tempuri.org/">
AND
<checkBarcode xmlns="http://tempuri.org" id="o0" c:root="1">
Do you have any idea how to solve this? I have the same problem, with a webservice that sends an image, but what I get is a blank image, probably because of this....