Problems with WindowsMobile.DirectX TextureLoader.FromFile

I'm trying to develop a simple application to my Omnia 2 in DirectX in VB.NET, but i stuck, really hard. I want to load a simple texture from a file, but the TextureLoader.FromFile gave me an InvalidCallException error. I don't know what to do, because the code is working on the emulator, but throw this error on the phone. I googled it, a lot, but found nothing.
I hope someone can help me in this.

Here's some code fragment. Please someone help me.

Code:

---

      Function InitializeGraphics() As Boolean
            Dim Parameters As PresentParameters = New PresentParameters()
            Parameters.Windowed = True
            Parameters.SwapEffect = SwapEffect.Discard
            DeviceForm = New Device(0, DeviceType.Default, Me, CreateFlags.None, Parameters)
            Me.OnCreateDevice(DeviceForm, Nothing)
            Return True
        End Function

        Private Sub OnCreateDevice(ByVal sender As Object, _
            ByVal e As EventArgs)
            Dim dev As Device = CType(sender, Device)
            spriteTexture = TextureLoader.FromFile(dev, "\Storage card\Picture.png")
            Using s As Surface = spriteTexture.GetSurfaceLevel(0)
                Dim desc As SurfaceDescription = s.Description
                textureSize = New Rectangle(0, 0, desc.Width, desc.Height)
            End Using
            sprite = New Sprite(DeviceForm)
        End Sub

---

Anybody? Please, I really need this to work. Nobody programming in DX? PLS!