Let me first describe my situation. I have a page with a custom control that appears multiple times. They load perfectly and work fine.
In each custom control, I have an iframe with the runat="server" attribute because I give each iframe a sequencial id in the querystring starting from 1 then 2 then 3 and so on.
In that iframe, I have an fileupload control that does a full postback on its html onchange event. A picture is then supposed to upload and be saved as a memory stream into a session variable. The session variable's name uses the numerical number from the id from the iframe's src's querystring. Then, with javascript, some image's src is changed to another aspx page that reads the memory stream and displays the image.
Looking at this as a whole, the basic concept is a preview of images the user wants to upload prior to the physical saving onto the harddisk.
My problem is that I get a "File does not exist" err ...
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