Close this window and refresh the calling page.

    Protected Sub ReturnButton_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles ReturnButton.Load
        If Request.UrlReferrer IsNot Nothing Then
            'Here we know this page was loaded as a result of the user clicking on a link from another page.
            ReturnButton.Visible = True
            'Provide JavaScript to refresh the calling page and close this page.
            'Doing this without a return page would cause a JavaScript error when the button is clicked because where wouldn't be an opener page to go back to.
            ReturnButton.OnClientClick = "window.opener.location.reload(); window.close()"
        Else
            ReturnButton.Visible = False
        End If
    End Sub