I'm trying to upgrade community edition 220.127.116.11 in response to the latest security alert. In Magento Connect Manager I search for update, then choose Mage_All_Latest upgrade to 18.104.22.168 and commit. Everything seems to be fine until I get an error telling me ./lib/Varien/Cache cannot be deleted and I should check permissions. these are 660. and in the apache error log I have: PHP Fatal error: Class 'Varien_Cache_Core' not found in /var/www/html/beadstore19/lib/Zend/Cache.php on line 195. The site is screwed and has to be restored. If I try to choose the upgrade to 22.214.171.124 instead (latest and greatest) after the install I get the installation screen telling me I will now download the latest updates, but this always fails and the site is totally screwed. OK, let's look at the first problem. Anyone any ideas?