I am following this tutorial: http://www.vbgamer.com/tutorial.asp?ndx=12
I did the first one about Initializing d3d first...
Here is my code with the error message in the Render sub.
  
Imports Microsoft.DirectX  
Imports Microsoft.DirectX.Direct3D  
  
Public Class Form1  
  
    Dim Dev As Device = Nothing  
    Private VertBuff As VertexBuffer  
    Private strings As String = "ASD"  
  
  
  
  
  
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load  
  
  
        If Init3ds() = False Then  
            MessageBox.Show("Awww.. No D3D for you!")  
        End If  
  
        Me.Show()  
        Do  
            Render()  
            Application.DoEvents()  
        Loop  
  
  
    End Sub  
  
    Public Function Init3ds() As Boolean  
        Try  
            Dim pParams As New PresentParameters()  
            pParams.Windowed = True  
            pParams.SwapEffect = SwapEffect.Discard  
            Dev = New Device(0, DeviceType.Hardware, Me, CreateFlags.SoftwareVertexProcessing, pParams)  
            Return True  
  
            MakeVerts()  
  
        Catch e As DirectXException  
            Return False  
        End Try  
    End Function  
  
    Private Sub Render()  
                                                  
        Try  
            Dev.Clear(ClearFlags.Target, System.Drawing.Color.Blue, 1.0F, 0)  
            Dev.BeginScene()  
                        Dev.SetStreamSource(0, VertBuff, 0)  
            Dev.VertexFormat = CustomVertex.TransformedColored.Format  
            Dev.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 1)  
                        Dev.EndScene()  
            Dev.Present()  
        Catch ex As DirectXException  
            Debug.WriteLine(ex)  
  
  
        End Try  
  
  
  
    End Sub  
  
  
    Public Sub MakeVerts()  
        VertBuff = New VertexBuffer(GetType(CustomVertex.TransformedColored), 3, Dev, 0, CustomVertex.TransformedColored.Format, Pool.Default)  
        Dim verts As CustomVertex.TransformedColored() = CType(VertBuff.Lock(0, 0), CustomVertex.TransformedColored())  
        verts(0).X = 150  
        verts(0).Y = 50  
        verts(0).Z = 0.5F  
        verts(0).Rhw = 1  
        verts(0).Color = Color.Aqua.ToArgb  
  
        verts(1).X = 250  
        verts(1).Y = 250  
        verts(1).Z = 0.5F  
        verts(1).Rhw = 1  
        verts(1).Color = Color.Brown.ToArgb  
  
        verts(2).X = 50  
        verts(2).Y = 250  
        verts(2).Z = 0.5F  
        verts(2).Rhw = 1  
        verts(2).Color = Color.LightPink.ToArgb  
  
        VertBuff.Unlock()  
    End Sub  
  
End Class