Of course the dummy uploader must be of the same type you use on your dynamic form. Also for  the dummy Uploader to make it not visible set the style="display:none;" so it won't be visible to the user.   Regards, Ben

Hi Qui,   I've seen this issue as I just started to search for a truly AJAXified FileUpload control. I believe you will see similar issue with any FileUpload control if loaded dynamically. The trick is (at least for me) to drop a "dummy" Uploader control to the ASPX page which is static and not dynamic, with just the ID and ...

Just tested another control from the CuteWebUI library: Uploader from the "Simple Upload withProgress" sample to see how it will behave. On a simple ASPX page it works just fine but again when loaded asynchronuously using an ASCX user control the Uploader kicks out the same "Object reference not set to an instance of an ...

Hi,   I have issue with the Uploader in a dynamically loaded user control in an UpdatePanel. When the user control is loaded in an async postback everything loads fine until I try to submit the file selected for uploading. I am using a UploadAttachments for uploading a single file with ManualStartUpload="true". When the associated ...