Without seeing your exact code it's difficult to tell. I've used code like that
shown below, which seems to work reliably. But to be honest, I've come to
prefer using the object model because the it's more programmer-friendly and less
quirky.


Private Sub ProcessDoclib(ByVal BaseUrl As String, ByVal ListName As String)

Dim listService As New localhost.Lists

listService.Url = strBaseUrl & "/" & _vti_bin/lists.asmx"

listService.Credentials = System.Net.CredentialCache.DefaultCredentials



Dim xmlDoc = New System.Xml.XmlDocument

Dim ndQuery As XmlNode = xmlDoc.CreateNode(XmlNodeType.Element, "Query", "")

Dim ndViewFields As XmlNode = xmlDoc.CreateNode(XmlNodeType.Element,
"ViewFields", "")

Dim ndQueryOptions As XmlNode = xmlDoc.CreateNode(XmlNodeType.Element,
"QueryOptions", "")



Try

Dim ndListItems As XmlNode = listService.GetListItems(strListName, Nothing,
ndQuery, _

ndViewFields, Nothing, ndQueryOptions)

Dim ds As New DataSet

Dim sr As New System.IO.StringReader(ndListItems.OuterXml)

ds.ReadXml(sr)

' Do whatever needs to be done...

Catch ex As System.Web.Services.Protocols.SoapException

Response.Write("Message:" + ControlChars.Lf + ex.Message + ControlChars.Lf + _

"Detail:" + ControlChars.Lf + ex.Detail.InnerText + ControlChars.Lf + _

"StackTrace:" + ControlChars.Lf + ex.StackTrace)

End Try

End Sub

One more inforamation regarding the error message i get, after the call to the
method of the webservice, my portal goes down though the site is still working.

On browsing to the Portal it gives a error message as:

You cannot view this area, either because the area no longer exists, or because
you do not have the rights to view this area. To change your rights, contact the
site administrator.

The snippet of the code where we are doing this is :


NetworkCredential credential= new
NetworkCredential("neha_singh02","great@2303","ITLINFOSYS"); // This is passed
to consume the webService, Search.asmx

listService.Credentials= credential;

try

{

//Code to get ID of the file from the document  Library





XmlDocument xmlDoc = new System.Xml.XmlDocument();

XmlNode syQuery = xmlDoc.CreateNode(XmlNodeType.Element,"Query","");

XmlNode syViewFields = xmlDoc.CreateNode(XmlNodeType.Element,"ViewFields","");

XmlNode syQueryOpt = xmlDoc.CreateNode(XmlNodeType.Element,"QueryOptions","");



//Build Queries

syViewFields.InnerXml = "<FieldRef Name='ID' /><FieldRef Name='Title'/>";

syQueryOpt.InnerXml = "<IncludeMandatoryColumns>FALSE</IncludeMandatoryColumns>"
+

"<DateInUtc>TRUE</DateInUtc>";

strXml= strXml+ "<Where><Eq><FieldRef Name='FileRef'/>" +

"<Value Type='Text'>" + fileUrl +"</Value></Eq></Where>";

syQuery.InnerXml =strXml;

//Get details from using the web  service

System.Xml.XmlNode ndListItems = listService.GetListItems("Restricted Access",
null, syQuery,