After updating our multisite setup to 4.1, anything under wp-admin gives 'NetworkError: 500 Internal Server Error'
Example
- "NetworkError: 500 Internal Server Error - http://sitewalla.com/wp-admin/network/plugins.php?plugin_status=upgrade"
- "NetworkError: 500 Internal Server Error - http://sitewalla.com/wp-admin/admin-ajax.php"
- recreated htaccess
- memory on php.ini is 128m
- updated wp-config.php 'WP_MEMORY_LIMIT' to 64
- Nothing came up with 'WP_DEBUG'