I'm having big problems with trying to update a record in a table based on a guid that I have in a hidden text field on my page. I keep getting a type conversion error, "Can Convert from string to uniqueidentifier. this is what my code looks like:

Sub UpdatePatient()
   Dim BillingQDS As DataSet = New DataSet
   Dim BillingQCB As SqlCommandBuilder
      Dim ConnectString1 As String
      Dim Connect1 As SqlConnection = New SqlConnection
      Dim Adapter1 As SqlDataAdapter = New SqlDataAdapter
   Dim Row1 as DataRow
   ConnectString1 = ConfigurationSettings.AppSettings("ConnectStr")
   Connect1.ConnectionString = ConnectString1
   'Adapter1.SelectCommand = New SqlCommand("Select * from tBillingQ where BillingQID = '" & Lbl_BillingQID.text  &"'" , Connect1)
   Adapter1.Fill(BillingQDS,"BillingQ")
   Row1 = BillingQDS.Tables("BillingQ").Rows(0)
   Row1.Item("Status") = 1
   Adapter1.Update(BillingQDS,"BillingQ")
  End Sub

<asp:label  ID="Lbl_BillingQID"  Visible="True" runat="server"/>