Index: wp-admin/setup-config.php
===================================================================
--- wp-admin/setup-config.php   (Revision 34707)
+++ wp-admin/setup-config.php   (Arbeitskopie)
@@ -53,7 +53,7 @@
        wp_die( '<p>' . sprintf( __( "The file 'wp-config.php' already exists. If you need to reset any of the configuration items in this file, please delete it first. You may try <a href='%s'>installing now</a>." ), 'install.php' ) . '</p>' );
 
 // Check if wp-config.php exists above the root directory but is not part of another install
-if ( file_exists(ABSPATH . '../wp-config.php' ) && ! file_exists( ABSPATH . '../wp-settings.php' ) )
+if ( @file_exists(ABSPATH . '../wp-config.php' ) && ! @file_exists( ABSPATH . '../wp-settings.php' ) )
        wp_die( '<p>' . sprintf( __( "The file 'wp-config.php' already exists one level above your WordPress installation. If you need to reset any of the configuration items in this file, please delete it first. You may try <a href='install.php'>installing now</a>."), 'install.php' ) . '</p>' );
 
 $step = isset( $_GET['step'] ) ? (int) $_GET['step'] : -1;
Index: wp-load.php
===================================================================
--- wp-load.php (Revision 34707)
+++ wp-load.php (Arbeitskopie)
@@ -36,7 +36,7 @@
        /** The config file resides in ABSPATH */
        require_once( ABSPATH . 'wp-config.php' );
 
-} elseif ( file_exists( dirname(ABSPATH) . '/wp-config.php' ) && ! file_exists( dirname(ABSPATH) . '/wp-settings.php' ) ) {
+} elseif ( @file_exists( dirname(ABSPATH) . '/wp-config.php' ) && ! @file_exists( dirname(ABSPATH) . '/wp-settings.php' ) ) {
 
        /** The config file resides one level above ABSPATH but is not part of another install */
        require_once( dirname(ABSPATH) . '/wp-config.php' );