SharePoint Web Service Lists.GetListCollection not returning all lists
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I'm using SharePoint's List web service and I tried GetListCollection but it's not returning all the lists. Here's my code (SBALists is my web reference name):

    Dim Lists As New SBALists.Lists
    Lists.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials
    Dim Result As XmlElement = Lists.GetListCollection
    Dim XR As New XmlTextReader(Result.OuterXml, XmlNodeType.Element, Nothing)
    Dim DS As New DataSet
    DS.ReadXml(XR)
    DataGridView1.DataSource = DS.Tables(0)

I also tried passing in my username/password for the credentials but doesn't change the results.

    Dim Cred As New Net.NetworkCredential("username", "password")
    Lists.Credentials = Cred

Any idea why some of the lists aren't returning?