I have an uncontrolled exception, I am using the digital person sdk on vb.net

This is the error that appears to me when verifying the footprint

  

DPFP.Error.SDKException: Event Handler has generated an Exception --- >

     

System.NullReferenceException: Object reference not set as   instance of an object. in SCCEE.Access.OnComplete (Object Capture,   String ReaderSerialNumber, Sample Sample) in   C: \ Users \ JEANCA \ Desktop \ Project \ SCCEE \ SCCEE \ Acceso.vb: line 100 in   DPFP.Capture.Capture.MessageReceived (Message & m) --- End of   Tracking the stack of the internal exception --- in   DPFP.Capture.Capture.MessageReceived (Message & m) in   DPFP.Capture.Capture.MessageEvents.MessageWindow.WndProc (Message & m)

While (read.Read())
 Dim memoria As New MemoryStream(CType(read("huella"), Byte()))
       template.DeSerialize(memoria.ToArray())
     verificador.Verify(caracteristicas, template, result)
     If (result.Verified) Then
           Nombre = read("Nombre")
          verificado = True
       Exit While
      End If
   End While