title: File Upload Error in MediaWiki 1.22.3 - Could not create directory "mwstore://local-backend/local-public/7/70"
body: <p>We recently upgraded our MediaWiki installation to 1.22.3 running on Ubuntu 12.04.2 LTS. Now when we try to upload files, we get the following error:</p>
  
  <p>Could not create directory "mwstore://local-backend/local-public/7/70"</p>