Hi,

          The picturebox does not have a transparent color property.  I
would use a form instead.

 Dim frm As Form

   Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles MyBase.Load
       PictureBox1.BackgroundImage = Image.FromFile("C:\bliss.bmp")
   End Sub

   Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Button1.Click
       Dim bm As New Bitmap(PictureBox1.Width, PictureBox1.Height)
       Dim g As Graphics = Graphics.FromImage(bm)
       g.Clear(Color.White)
       g.FillEllipse(Brushes.Red, 20, 20, 20, 20)
       bm.MakeTransparent(Color.White)
       g.Dispose()
       frm = New Form
       With frm
           .FormBorderStyle = FormBorderStyle.None
           .Size = PictureBox1.Size
           .TopLevel = False
           .Parent = PictureBox1
           .BringToFront()
           .TransparencyKey = SystemColors.Control
           .BackgroundImage = bm
           .Show()
       End With
   End Sub

Ken
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