cullenrc:
I think you're on to something there as I've just managed to "break" the sample "Framework 2.0-Csharp-MicrosoftAjax/multiple-files-upload.aspx"
If you move the server Form, Script Manager and Update Panel tags from the Master page and place them directly into the content of page multiple-files-upload.aspx, you get the error message that we are all experiencing.
cullenrc,
I did it but it still work for me.
Can you just send us a sample project showing this issue?
Thanks.
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