LinuxQuestions.org - [SOLVED] Googlebot blocked

Please help us, our forum very much depends on being indexed by Google.

As of October 1, Googlebot suddenly cannot access our forum at http://www.spywareinfoforum.com.
I know of nothing that changed on the server that day.

We do not seem to have ModSecurity - locate doesn't report any.

I don't find any likely address banned in iptables. Adding this line at the top of INPUT hasn't helped:
ACCEPT all -- 66.249.64.0/19 anywhere

The error that Googlebot gets (using Fetch as Googlebot in Webmaster Tools):

Quote:

HTTP/1.1 403 Forbidden
Date: Fri, 05 Oct 2012 22:43:32 GMT
Server: Apache/2
Content-Length: 406
Keep-Alive: timeout=1, max=100
Connection: Keep-Alive
Content-Type: text/html; charset=iso-8859-1

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>403 Forbidden</title>
</head><body>
<h1>Forbidden</h1>
<p>You don't have permission to access /index.php
on this server.</p>
<p>Additionally, a 403 Forbidden
error was encountered while trying to use an ErrorDocument to handle the request.</p>
<hr>
<address>Apache/2 Server at www.spywareinfoforum.com Port 80</address>
</body></html>

The messages in /var/log/httpd/domains/spywareinfoforum.com.error.log say:

Quote:

[Sat Oct 06 14:07:32 2012] [error] [client 66.249.71.38] client denied by server configuration: /home/mike/domains/spywareinfoforum.com/public_html/index.php

What does that mean? What server configuration? Where? I believe it is IP specific since I have no problem accessing our forum as guest. I have no idea where to look.

We have CentOS 5.5