code behind of conrol not accesible

hello, i'm using VS2005 and when i drag and drop an image button, i can't access it from code behind.
the following is an example of an unaccessible imagebutton
<asp:ImageButton runat="server" ID="ImgIn" ImageUrl="~/images/InWork.JPG" Visible="false" ToolTip='<%#DateTime.Now.ToString("HH:mm")%>' OnClick="ImgIn_Click" OnClientClick="DoSomething();" />10x.
 
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