AsyncFileUpload fails in hidden panel

Could someone help: I have the AsyncFileUpload controk within a <Panel>
control that I toggle visibility True/False.

For Example when the page loads pnlEdit.visible = False. Then when a user
clicks on a detail record in a grid I display the panel with the
AsyncFileControl ie: pnlEdit.Visible = True.

Because the the AsyncFileUpload Control is not displayed on the page right
away it errors when you try to upload a file. Would anyone know how I could
preload the control or configure it

to work in this configuration?



ie:

<asp:UpdatePanel ID="updEditDetails" runat="server" UpdateMode="Always">

<ContentTemplate>

<asp:Panel ID="pnlEdit" runat="server">

<cc1:AsyncFileUpload ID="FileUpload" runat="server"
width="200px"/>

</asp:Panel>

</ConTentTemplate>

</asp:UpdatePanel>





Thanks