B1if - Web Service with Server Error

Hi, Guys.

If anyone can help me thank you.

I did all the configuration in B1if to use the option of Inbound "Web Service Call", I created a windows form project in Visual Basic in Visual Studio 2010 and added the reference of the WSDL that I have begotten in my B1if, but when performing the same occurs error "Server error" at the time of "response", does anyone have idea what could be??

Since I thank you,