What does this error log even mean?

I got this back from google Adwords who explained they could not allow ads on my开发者_StackOverflow website because of an invalid HTTP response code. This comes as a surprise because the site loads perfectly alright, and in my debugger, I can not find any return errors at all.

The error they sent:

http://www.spanishtavern.com/home.html
Start Time: Mon Jul 25 2011 15:51:12 GMT-0400 (Eastern Daylight Time)
t=1311623472198 [st=  0] +REQUEST_ALIVE                           
[dt=157]
t=1311623472198 [st=  0]     URL_REQUEST_START_JOB                  [dt=
1]
                             --> load_flags = 1114240 (ENABLE_LOAD_TIMING
| MAIN_FRAME | VERIFY_EV_CERT)
                             --> method = "GET"                  
                             --> priority = 0                    
                             --> url =
"http://www.spanishtavern.com/home.html"
t=1311623472199 [st=  1]    +URL_REQUEST_START_JOB                
[dt=153]
                             --> load_flags = 1114240 (ENABLE_LOAD_TIMING
| MAIN_FRAME | VERIFY_EV_CERT)
                             --> method = "GET"                  
                             --> priority = 0                    
                             --> url =
"http://www.spanishtavern.com/home.html"
t=1311623472199 [st=  1]        HTTP_CACHE_GET_BACKEND              [dt=
0]
t=1311623472199 [st=  1]        HTTP_CACHE_OPEN_ENTRY               [dt=
0]
                                --> net_error = -2 (FAILED)      
t=1311623472199 [st=  1]        HTTP_CACHE_CREATE_ENTRY             [dt=
0]
t=1311623472199 [st=  1]        HTTP_CACHE_ADD_TO_ENTRY             [dt=
0]
t=1311623472199 [st=  1]       +HTTP_STREAM_REQUEST                 [dt=
52]
t=1311623472251 [st= 53]           HTTP_STREAM_REQUEST_BOUND_TO_JOB 
                                   --> source_dependency =
{"id":80949,"type":11}
t=1311623472251 [st= 53]       -HTTP_STREAM_REQUEST                
t=1311623472251 [st= 53]       +HTTP_TRANSACTION_SEND_REQUEST       [dt=
0]
t=1311623472251 [st= 53]           HTTP_TRANSACTION_SEND_REQUEST_HEADERS 
                                   --> GET /home.html HTTP/1.1   
                                       Host: www.spanishtavern.com
                                       Connection: keep-alive    
                                       User-Agent: Mozilla/5.0 (Windows NT
6.1; WOW64) AppleWebKit/534.30 (KHTML, like Gecko) Chrome/12.0.742.122
Safari/534.30
                                       Accept:
text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
                                       Accept-Encoding: gzip,deflate,sdch
                                       Accept-Language: en-US,en;q=0.8
                                       Accept-Charset:
ISO-8859-1,utf-8;q=0.7,*;q=0.3
t=1311623472251 [st= 53]       -HTTP_TRANSACTION_SEND_REQUEST      
t=1311623472251 [st= 53]       +HTTP_TRANSACTION_READ_HEADERS     
[dt=101]
t=1311623472251 [st= 53]           HTTP_STREAM_PARSER_READ_HEADERS
[dt=101]
t=1311623472352 [st=154]           HTTP_TRANSACTION_READ_RESPONSE_HEADERS

                                   --> HTTP/1.1 404 Not Found    
                                       Date: Mon, 25 Jul 2011 19:51:12 GMT
                                       Server: Apache/2.2.3 (Red Hat)
                                       X-Powered-By: PHP/5.1.6   
                                       P3P: CP="NOI NID ADMa OUR IND UNI
COM NAV"
                                       Cache-Control: private,
must-revalidate
                                       Set-Cookie: [value was stripped]
                                       Set-Cookie: [value was stripped]
                                       Content-Length: 5431      
                                       Connection: close         
                                       Content-Type: text/html;
charset=UTF-8
t=1311623472352 [st=154]       -HTTP_TRANSACTION_READ_HEADERS      
t=1311623472352 [st=154]        HTTP_CACHE_WRITE_INFO               [dt=
0]
t=1311623472352 [st=154]        HTTP_CACHE_WRITE_DATA               [dt=
0]
t=1311623472352 [st=154]        HTTP_CACHE_WRITE_INFO               [dt=
0]
t=1311623472352 [st=154]    -URL_REQUEST_START_JOB                 
t=1311623472352 [st=154]     HTTP_TRANSACTION_READ_BODY             [dt=
0]
t=1311623472352 [st=154]     HTTP_CACHE_WRITE_DATA                  [dt=
0]
t=1311623472354 [st=156]     HTTP_TRANSACTION_READ_BODY             [dt=
0]
t=1311623472354 [st=156]     HTTP_CACHE_WRITE_DATA                  [dt=
0]
t=1311623472354 [st=156]     HTTP_TRANSACTION_READ_BODY             [dt=
0]
t=1311623472354 [st=156]     HTTP_CACHE_WRITE_DATA                  [dt=
0]
t=1311623472354 [st=156]     HTTP_TRANSACTION_READ_BODY             [dt=
1]
t=1311623472355 [st=157]     HTTP_CACHE_WRITE_DATA                  [dt=
0]
t=1311623472355 [st=157] -REQUEST_ALIVE

I apologize for being daft, but I can't make heads or tails of this error, let alone, where it's coming from. Any ideas?

Somewhere you must have a link to home.html which doesn't exist. (This is on your main splash page)

Your homepage is actually located at home.php

If you visit the url in the log they've sent: http://www.spanishtavern.com/home.html you'll see that you're actually on the 404 page. (look in firebug and you'll see the request to home.html returning a 404)

To add to the confusion, your 404 page always redirects to the homepage. With a url like home.html redirecting you to the homepage, this could easily be missed as being a 404.

The error they get is the 404 response code:

--> HTTP/1.1 404 Not Found

home.html can not be found.

I tried doing the same using netcat and also got a 404 response:

$ nc www.spanishtavern.com 80
GET /home.html HTTP/1.0

HTTP/1.1 404 Not Found
Date: Mon, 01 Aug 2011 13:41:26 GMT
Server: Apache/2.2.3 (Red Hat)
Content-Length: 280
Connection: close
Content-Type: text/html; charset=iso-8859-1

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>404 Not Found</title>
</head><body>
<h1>Not Found</h1>
<p>The requested URL /home.html was not found on this server.</p>
<hr>
<address>Apache/2.2.3 (Red Hat) Server at default Port 80</address>
</body></html>