PHP/IIS Integrated Pipeline Anonymous Visitor HTTP Posts Timeout

I have configured PHP to run under FastCgi on IIS7 on Windows Server 2008 under Forms Authentication/IIS Integrated Pipeline. PHP and even Drupal is working brilliantly for authenticated users. For anonymous requests however, all PHP Posts hang until the PHP Timeout and then return a 500.0 Error. No error appears in the log, and the error returned to screen isn't too helpful even with verbose logging turned on:

 Internet Information Services 7.5
 Error Summary HTTP Error 500.0 - Internal Server Error C:\Program Files (x86)\PHP\php-cgi.exe - The FastCGI process exceeded configured request timeout Detailed Error Information
 Module        FastCgiModule
 Notification  ExecuteRequestHandler
 Handler       PHP_via_FastCGI Error
 Code          0x80070102 
 Requested URL http://localhost/application/test.php
 Physical Path D:\Websites\application\test.php 
 Logon Method  Anonymous 
 Logon User    Anonymous

All authenticated requests work fine, and the second I change the web.config authentication type from "Forms" to "Windows" or "None" Anonymous PHP Posts work. But this doesn't solve the problem because then no one is authenticated. ASP.Net and Classic ASP Posts work under the same configuration that PHP anonymous Posts are failing.

Just a few of the things I've tried include...

Added and removed the FormsAuthentication Module in the local web.config (though already inherited):

<modules>
    <remove name="FormsAuthentication" />
    <add name="FormsAuthentication" type="System.Web.Security.FormsAuthenticationModule" preCondition="" />
</modules>

Explicitly Allowed Access (though already inherited):

<authorization>
    <add accessType="Allow" users="*" verbs="GET, POST" />
</authorization>

Tweaked the PHP.ini settings, currently set to:

default_socket_timeout = 60
upload_tmp_dir="C:\Windows\Temp"
session.save_path="C:\Windows\Temp"
log_errors = On
error_log="C:\Windows\temp\php-errors.log"
cgi.force_redirect=0
fastcgi.impersonate=1
cgi.fix_pathinfo=1
fastcgi.logging=0
max_execution_time=30
extension_dir="C:\Program Files (x86)\PHP\ext"
error_reporting = E_ALL & ~E_NOTICE
display_errors = On
max_input_time = 60
memory_limit = 128M
post_max_size = 10M   

Changed the Application Pool Identity from ApplicationPoolIdentity to NetworkService to Administrator accounts. All gave the same behavior.

I have followed the PHP.ini and web.config settings recommended on MSDN (http://msdn.microsoft.com/en-us/magazine/cc135973.aspx) and IIS.Net (http://learn.iis.net/page.aspx/246/using-fastcgi-to-host-php-applications-on-iis-7/).

When I say a simple PHP Post fails, I mean simple:

<form action="test.php" method="post">
   <input type="text" name="testpost" />
   <input type="submit" value="postit" />
</form>
<?php if(isset($_POST['testpost'])) { ?>
   Posted: <?php echo($_POST['testpost']) ?>
<?php } else { ?>
   Waiting for post...
<?php } ?>

The only reference I have found to this problem online is an unanswered question on Experts Exchange (http://www.experts-exchange.com/Software/Server_Software/Web_Servers/Microsoft_IIS/Q_26706716.html).

I am new to PHP and IIS7, so after several weeks tinkering with this on and off, I figured it was finally time to ask to see what simple thing is I must be overlooking.

Anyone have any ideas?

Thanks!

Did you try to set the application pool to "Classic" managed pipeline mode instead of the integrated?