Zend Optimizer not installed Error After server upgrade. You can check and see if your server has been upgraded yet here:
http://www.dreamhoststatus.com/
If you are seeing this error:
Zend Optimizer changed its name to Zend Guard between PHP version 5.2 and 5.3. Files encoded with Zend Optimzer using PHP 5.2 aren’t compatible with Zend Guard using PHP 5.3+. As you know our servers have been upgraded and PHP 5.2 is no longer supported. To ensure a smooth transition to 5.4, you will need to make sure your files are encoded to work with Zend Guard. It’s rather simple to activate Zend Guard using a custom phprc file, and instructions for that can be found here: