C# – How to copy a file into SharePoint using a WebService

I am writting a winforms c# 2.0 application that needs to put an XML file into a document library on SharePoint.

I want to use a WebService instead of using the object model (no sharepoint.dll to reference here)

I am currently using the http://webserver/site/_vti_bin/copy.asmx webservice.

Here is some code:

byte[] xmlByteArray;
using (MemoryStream memoryStream = new MemoryStream())
{
    xmlDocument.Save(memoryStream);
    xmlBytes = memoryStream.ToArray();
}

string[] destinationUrlArray = new string[] {"http://webserver/site/Doclib/UploadedDocument.xml"};

FieldInformation fieldInfo = new FieldInformation();
FieldInformation[] fields = { fieldInfo };


CopyResult[] resultsArray;

using (Copy copyService = new Copy())
{
    copyService.Credentials = CredentialCache.DefaultCredentials;
    copyService.Url = "http://webserver/site/_vti_bin/copy.asmx";

    copyService.Timeout = 600000;

    uint documentId = copyService.CopyIntoItems("", destinationUrlArray, fields, xmlByteArray, out resultsArray);
}

When this code runs, I get a single result in the resultsArray out parameter:

DestinationURL: "http://webserver/site/Doclib/UploadedDocument.xml"
ErrorCode: UnKnown
ErrorMessage: "Object reference not set to an instance of an object."  

From my searching, I have found a couple of possible helps.

• Microsoft TechNet — "The copy.asmx copyintoitems will only work if the source and destination urls are in the same SPWebApplication (Site Collection)."

• Microsoft Social — "Object reference not set to an instance of an object
  error occurs because of SharePoint not able to identified that particular property."

This leads me to believe my source url should be set to something, but what? This is originating from a client workstation and does not have a source URL.

Any help would be appricated.

hank you,
Keith