LightZA

Solution from: http://forge.prestashop.com/browse/PSCFV-4573 (see comments) in /controllers/admin/AdminStatsController.php change 'class AdminStatsControllerCore extends AdminStatsTabControllerCore' to 'class AdminStatsControllerCore extends AdminStatsTabController' Hope this works for you guys.

I had that but on an upgrade. Cleared my browser cache and it started behaving.

Suffering the same problem after an upgrade from 1.4.x, it's just the stats page itself, seach engines and reffers under statsdrop down menu are working for me, getting blank screen on Firefox and 500 error on IE.