the webserver answers with status codes but they are invisible for you. i think they are named as http header.
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this is ok , i read the index.html
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HTTP/1.0 200 OK
Date: Sat, 23 Feb 2013 17:04:35 GMT
Expires: -1
Cache-Control: private, max-age=0
Content-Type: text/html; charset=ISO-8859-1
Set-Cookie: NID=67=Zm-HNe7XtiaSEJxw6Ys8hxGK_ClnaKWnM8Ab1OsBwUR8-Yd5jlWOJ8BIsM_y4_1vmaANkXXjJw-Gf37OOIHgRJxScNp66HIVOnrWqf6AIciJWWP_68cNll90f1PwAXEQ; expires=Sun, 25-Aug-2013 17:04:35 GMT; path=/; domain=.; HttpOnly
P3P: CP="This is not a P3P policy! See http://www.google.com/support/accounts/bin/answer.py?hl=en&answer=151657 for more info."
Server: gws
X-XSS-Protection: 1; mode=block
X-Frame-Options: SAMEORIGIN
<!doctype html><html itemscope="itemscope" itemtype="http://schema.org/WebPage"><head><meta itemprop="image" content="/images/google_favicon_128.png"><title>Google</title><script>(function(){
window.google={kEI:"o_YoUdb4BoXYtQacqYBQ",getEI:function(a){for(var b;a&&(!a.getAttribute||!(b=a.getAttribute("eid")))
a=a.parentNode;return b||google.kEI},https:function(){return"https:"==window.location.protocol},kEXPI:"25657,39523,4000116,4001569,4001947,4001959,4001975,4002001,4002159,4002562,4002734,40...
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this is file not found if ask for ...
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HTTP/1.0 404 Not Found
Content-Type: text/html; charset=UTF-8
X-Content-Type-Options: nosniff
Date: Sat, 23 Feb 2013 17:01:20 GMT
Server: sffe
Content-Length: 947
X-XSS-Protection: 1; mode=block
<!DOCTYPE html>
<html lang=en>
<meta charset=utf-8>
<meta name=viewport content="initial-scale=1, minimum-scale=1, width=device-width">
<title>Error 404 (Not Found)!!1</title>
<style>
*{margin:0;padding:0}html,code{font:15px/22px arial,sans-serif}html{background:#fff;color:#222;padding:15px}body{margin:7% auto 0;max-width:390px;min-height:180px;padding:30px 0 15px}* > body{background:url(//www.google.com/images/errors/robot.png) 100% 5px no-repeat;padding-right:205px}p{margin:11px 0 22px;overflow:hidden}ins{color:#777;text-decoration:none}a img{border:0}@media screen and (max-width:772px){body{background:none;margin-top:0;max-width:none;padding-right:0}}
</style>
<a href=//www.google.com/><img src=//www.google.com/images/errors/logo_sm.gif alt=Google></a>
<p><b>404.</b> <ins>That’s an error.</ins>
<p>The requested URL <code>/esistnichtda.png</code> was not found on this server. <ins>That’s all we know.</ins>
