Do not use the 'TextBox' - work directly with the Richtextbox - It works
Dim img As Bitmap
img = CType(Image.FromFile("C:\Documents and Settings\laoai\My Documents\My Pictures\test.jpg"), Bitmap)
Clipboard.Clear()
Clipboard.SetDataObject(img, False)
RichTextBox2.Paste(DataFormats.GetFormat(DataFormats.Bitmap)) 'No RichTextBox2.TextBox.Paste ...