Get the detailed error message from Microsoft.SharePoint.SoapServer.SoapServerException

Remove all try and catch statements and let the error come as "SoapException was unhandled by code" error. In this case debugging will throw a message. See this message and click on ViewDetail under Action.

Under the View Detai, expand exception. See InnerXML under Detail: you will get the exact error. For example, I am getting this error from Microsoft.SharePoint.SoapServer.SoapServerException: "There is no Web named \"/sites/VendorDocumentCenter\".".

See the attached Image for more detail.

I hope this will help you to see detail error of Microsoft.SharePoint.SoapServer.SoapServerException

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