WordPress MU

I am trying to upgrade from 2.6 to 2.7.1, and am getting the white screen of death. I have followed instructions carefully, but when I try to login after the upgrade, I just get the white screen as though there is a php error somewhere.

Here is the code from the updated config file (less the proprietary info):

<?php
/* Don't try to create this file by hand. Read the README.txt and run the installer. */
// ** MySQL settings ** //
define('WP_CACHE', true); //Added by WP-Cache Manager
define('DB_NAME', ' ');    // The name of the database
define('DB_USER', ' ');     // Your MySQL username
define('DB_PASSWORD', ' '); // ...and password
define('DB_HOST', 'localhost');    // 99% chance you won't need to change this value
define('DB_CHARSET', 'utf8');
define('DB_COLLATE', '');
define('VHOST', 'yes');
$base = '/';

define('DOMAIN_CURRENT_SITE', 'mysite.com');
define('PATH_CURRENT_SITE', '/');
define('BLOGID_CURRENT_SITE', '1');

define('ADMIN_COOKIE_PATH', '/');
define('COOKIE_DOMAIN', '');
define('COOKIEPATH', '');
define('SITECOOKIEPATH', '');

define('AUTH_KEY', 'ea03fa851991ed587ca72aaa35803b59256411a52186b48247ce29e679a44821');
define('SECURE_AUTH_KEY', 'fc6de68293316f3ea39103d3406aedec4565d22991fabe8de1fd319e39b51ea4');
define('SECURE_AUTH_SALT', '611832e5fbf36e23ebda0001837e9f6bcd925119b3c0bad9aa000fd4d83c96bc');
define('NONCE_KEY', 's*NGohlA?KaB-<I*@YW8]JZvzDiicB66.|~64MrYD55TItV,Uxw[V[wKpCX?ws54');
define('AUTH_SALT', 'lIZuOgxC.=kV1wB>xB*+x!4muPE|h1tgB!{X./NEOt.Zv(KC&;>GEc&Z= >fL$=r');
define('LOGGED_IN_KEY', '7c98a32c1160b6535c888e8b73b793afe0d83b089eefaa7e6dec0700d25e1e8e');
define('SECRET_KEY', 'eac77c13d39b0f53bae58fa295047c53dd6466caf6a6c5098b60f35fce136c18');
define('SECRET_SALT', '02e198b593c06aa540439c3e2dad8bf06997c162488df6d0fb365398f61a2f2a');
define('LOGGED_IN_SALT', '97d142ffda5f73e41923b78ce9ba3d780fadd366abbccdd021b508ba7fa4262e');

// double check $base
if( $base == 'BASE' )
	die( 'Problem in wp-config.php - $base is set to BASE when it should be the path like "/" or "/blogs/"! Please fix it!' );
// You can have multiple installations in one database if you give each a unique prefix
$table_prefix  = 'wp_';   // Only numbers, letters, and underscores please!

// Change this to localize WordPress.  A corresponding MO file for the
// chosen language must be installed to wp-content/languages.
// For example, install de.mo to wp-content/languages and set WPLANG to 'de'
// to enable German language support.
define ('WPLANG', '');

// uncomment this to enable wp-content/sunrise.php support
define( 'SUNRISE', 'on' );

// Uncomment and set this to a URL to redirect if a blog does not exist or is a 404 on the main blog. (Useful if signup is disabled)
// For example, browser will redirect to http://examples.com/ for the following: define( 'NOBLOGREDIRECT', 'http://example.com/' );
// define( 'NOBLOGREDIRECT', '' );

define( "WP_USE_MULTIPLE_DB", false );

/* That's all, stop editing! Happy blogging. */

if ( !defined('ABSPATH') )
	define('ABSPATH', dirname(__FILE__) . '/');
require_once(ABSPATH . 'wp-settings.php');
?>

Thanks in advance!

Could you check your webserver's error logs to see what's in there? That's a good habit to get into no matter what software you;re running.

A search though should show you that white screen usually means a problem with a plugin. Try renaming the plugins and mu-plugins subdirectories to see if that helps.

edit: Oh, and which set of upgrade instructions are you following?

I am following the instructions posted here:

http://codex.wordpress.org/Upgrading_WPMU (2.6 to 2.7)

I renamed all of the plugin subdirectories but no luck.

The log files are not revealing...

O, and I think I only have 2.6, not 2.6.5, but do not see any upgrade instructions for going from 2.6 to 2.6.5...

Also, there are no errors in the apache or php error logs...