When I upload a file which size is less than 1M,it could be upload success,but when I upload a bigger file,it failed,display information is :"the page cannot be displayed"(¸ÃÒ³ÎÞ·¨ÏÔʾ),I used HtmlControls.HtmlInputFile or WebClient to upload the file if the file's size is small.
how can I solve the problem if I want to upload the bigger file.
Can you help me ? thank you.

Change the maxRequestLength in web.config to get file size more than 1M.
<httpRuntime maxRequestLength="128"/>