写真のような状況になった理由を教えていただけますか？

$url = 'http://www.wanpusoft.com/weixin/Web/index.html';<br />print_r(get_headers($url));<br /><br />$url = 'http://www.wanpusoft.com/weixin/Wechar';<br />print_r(get_headers($url));

Array<br />(<br />    [0] => HTTP/1.1 200 OK<br />    [1] => Cache-Control: max-age=1296000<br />    [2] => Content-Type: text/html<br />    [3] => Last-Modified: Thu, 23 Apr 2015 07:53:40 GMT<br />    [4] => Accept-Ranges: bytes<br />    [5] => ETag: "30f6d99c9a7dd01:0"<br />    [6] => Server: Microsoft-IIS/7.0<br />    [7] => X-Powered-By: ASP.NET<br />    [8] => Date: Thu, 30 Apr 2015 07:28:33 GMT<br />    [9] => Connection: close<br />    [10] => Content-Length: 8746<br />)<br />Array<br />(<br />    [0] => HTTP/1.1 404 Not Found<br />    [1] => Cache-Control: private<br />    [2] => Content-Length: 1898<br />    [3] => Content-Type: text/html; charset=utf-8<br />    [4] => Server: Microsoft-IIS/7.0<br />    [5] => X-AspNet-Version: 4.0.30319<br />    [6] => X-Powered-By: ASP.NET<br />    [7] => Date: Thu, 30 Apr 2015 07:28:34 GMT<br />    [8] => Connection: close<br />)<br /><br />