AsyncFileUpload is not working with coockiless session as PostbackURL is going without appending session in URL. So, session_start event is getting execute when user trying to upload any document. Getting "server error" in response.
For now I have solved this problem by creating a dynamic postback url (protected variable in class file) and setting this dynamic URL for the control before starting the Upload but this should be handled in control itself.
For now I have solved this problem by creating a dynamic postback url (protected variable in class file) and setting this dynamic URL for the control before starting the Upload but this should be handled in control itself.