rspercy60, if you're still interested in drag/drop, here's a way to do it from Windows Explorer. I made it quite minimalist -- no error checking for the specified filetype, for instance, but that is somewhat dependent on your environment and usage, and should be easy to add anyway. Hope it helps!
Public Class Form1
Private Sub TextBox1_DragEnter(ByVal sender As System.Object, _
ByVal e As System.Windows.Forms.DragEventArgs) _
Handles TextBox1.DragEnter
If (e.Data.GetDataPresent(DataFormats.FileDrop)) Then
e.Effect = DragDropEffects.Copy
Else
e.Effect = DragDropEffects.None
End If
End Sub
Private Sub TextBox1_DragDrop(ByVal sender As System.Object, _
ByVal e As System.Windows.Forms.DragEventArgs) _
Handles TextBox1.DragDrop
TextBox1.Text = e.Data.GetData(DataFormats.FileDrop)(0)
RichTextBox1.Text = My.Computer.FileSystem.ReadAllText(TextBox1.Text)
TabControl1.SelectTab(1)
End Sub
End Class