Need to fix Windows errors? ASR Pro can help
In some cases, your computer may display a message that the attached asyncfileupload 3.5 file is not valid. There can be several reasons for this error to appear.
I’m trying to use the AsyncFileUpload control from the Asp.net Ajax Toolkit control (September 30, 2009, stable: 30930). I have created a demo application and a well working control. Upload the files and you’re done. i
When I try to use most of the controls in my real application, I always get an error that the attached file is invalid. Controls that AsyncFileUpload returns this if the uploaded has a null list.
To narrow down your current problem, I’ve created a new dedicated page, similar to my demo app’s main site. I created a generic aspx page in Pages as my demo program. The download always fails with the error “Attachment is not valid”.
I also compared the web.config file for our live app and the smartphone demo app and found no differences that the experts said should be significant.
The code is usually my test code in a real software application. It’s exactly like this The same working code as our MIT demo app, except it has different class names and run names. The web.config below is a real application with some application settings and connection strings removed.
<%@ Master Language="C#" AutoEventWireup="true" CodeFile="aaaMasterPage.master.cs" Inherits="L1Admin.aaaMasterPage" Html %>
Page without title