System Configuration page blank - SOLVED

After upgrading to 1.9.0.1 I got blank page...

  1. Close the Admin Panel browser window.
  2. As a user with root privileges, delete all files except config.xml from the following >directory: magento-install-dir/app/code/core/Mage/GoogleCheckout/etc
  3. When you log back in to the Admin Panel, everything works as expected. If you're still encountering errors, see Getting Help With Your Installation or Upgrade.