Hi vincentUCF,

Do you get the same problem on http://www.ajaxuploader.com/Demo/Large-File-Upload.aspx? I can not reproduce this issue. 

And you can try catch the error, and handle it by your own logic, and do not show any alert. More details please refer to http://www.ajaxuploader.com/document/scr/html/How-to-catch-uploader-error.htm 

Regards,

Ken