file size is too large

When I try to upload a file which is bigger than 10MB, it pops up alert that the filesize is too large, the maximum file size allowed is set to 10.00MB.  However, if I used a regular file upload control, I can upload large file more than 10 MB.  My web.config sets the correct maxAllowedContentLength according to the article at

http://ajaxuploader.com/large-file-upload-iis-asp-net.htm 

Please advice what I can do to correct this issue.

Thanks