This
article gives all you need to create a custom web serice in SharePoint 2007. But when adding a custom service in Visual Studio 2008, get the following error:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgAtIkN_vLZTymor3DespCs5PHbfoMVnY6u7nj76H8wbnujCk192MVcBekUL94e1t0l7vGjNR-iA6z8gZ_3-jY3AnR56eWkRSpkpeV7CtOoMe_-mlURAOmGqHrfBTExiRKpjNe-9Tt0cAPr/s320/error.bmp)
It turns out you have to append ?WSDL :
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj8aTgJDIeK7p5kMLn6IT-I_3_JrFoxL75rWswx0Zkk3wEMu_nKZnmQp_9_EPCLKoULTl6e1S3EhnyqdlT_N1OdEF-zMnsKO-yjgrlXe4Gr0auqtQSEaEp9x_An5sftJzlPwRX5XuAhyphenhyphen8OO/s320/noError.bmp)
A custom sharepoint web service needs to be put in _vti_bin to be trusted. Otherwise either SharePoint trust level or CAS policy need to be modified.