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If you are installing the calendar for the first time:
Zend Optimizer is a server level program that must be installed by a web host provider or server administrator. It is freely available for download from www.zend.com. You must install the correct version that properly matches the version of PHP that is installed on the server. You can test if Zend Optimizer is working by running our tester script from the support page of this web site.
If see this error after the calendar was already working:
This can only be caused by four possible issues.
- The version of PHP on the server was upgraded and the Zend Optimizer is not the correct version for the new installation of PHP. Your web host provider or server administrator will need to update Zend Optimizer for you. You can test if Zend Optimizer is working by running our tester script from the Free Download page of this web site. *NOTE: At the time of this FAQ, PHP 5.3 is not supported by Zend Optimizer.
- A configuration change on the server has disabled Zend Optimizer. Your web host provider or server administrator will need to update the server configuration to enable Zend Optimizer. You can test if Zend Optimizer is working by running our tester script from the Free Download page of this web site.
- Some servers allow changes to be made by inserting special code into php.ini or .htaccess files in the directory structure of your web site. These may be disabling Zend Optimizer. You may need to add one of these files to your calendar directory to enable Zend Optimizer. You web host provider or server administrator should know how to fix this for you.
- In some rare cases, another module that loads with PHP can cause a conflict with Zend Optimizer. Check with your web host provider or server administrator and see if any new modules were recently added and they would need to work on a solution to resolve the conflict.
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