> 	Private Sub Button1_Click(ByVal sender As System.Object, ByVal e 
As System.EventArgs) Handles Button1.Click
>
>         	Dim i As Integer
	> 	Label1.Text ="Downloading please wait"
	> 	Label1.Visible = True
 >        	
	> 	For i = 0 To 100
	>             Response.Write(i & "<BR>")
 >       		Next

>         	Label1.Text = "Download successful."
 >        
 >    	End Sub

This is a web application, isn't it?  The HTML isn't sent to the client 
until the event completes, which is why you'll see the 'Successful' 
message but not the 'Wait' message.  

Use some DHTML to change the text in the <SPAN>.  Give the <SPAN> an ID, 
then use JavaScript in the button click.  You'll have to modify the HTML 
in the ASPX page.  You might have a <BUTTON> or an <INPUT> -- you'll have 
to look at the HTML.  The onClick event is the same either way:

<INPUT type="submit" onclick="document.all.SPANID.innerText = 'Downloading 
Data...please wait...'">

'SPANID' is whatever you have named your Label control.  When the download 
is complete, the page will refresh and the 'Successful' message will 
show.  That ought to do it.

Robert Herrick