I'm developing a website using .NET 3.5 and I'm having problems with the asyncfileupload control.

The problem occurs when you upload a file, and then try upload the same file again. On the second upload, none of the clientside nor serverside methods fire. Everything works fine if you upload one file, upload a file with a different name and then upload the first one again.

This is a bit of a pain because on the page I allow the user to delete the uploaded images so I need the functionality to upload a file with the same name as the previous upload.

Has anyone else encountered this and are there any work arounds?


In case anyone stumbles upon this in the future, I managed to solve this by clearing the value of the input elements that the ASyncFileUpload control creates. E.g.

function clearContents() {
        var AsyncFileUpload = $get("<%=asyncImage.ClientID%>");
        var txts = AsyncFileUpload.getElementsByTagName("input");

        for (var i = 0; i < txts.length; i++) {
            //type == "file" is what is needed to clear the value
            if (txts[i].type == "hidden" || txts[i].type == "file") {
                txts[i].value = "";

The reason why this was so tricky is that in "View Source Chart" (a Firefox plugin that displays the rendered rouce of a page) wasn't showing the value for this input, so I assumed it was empty already!

I am facing the same problem that Asyncfileupload won't upload same file twice
if you acheived the solution for this please share the details on that.
Thanks in advance.