If you are having trouble or issues with ZOO, this can have numerous causes. ZOO has a build in system check, to detect some of the problems. But there are some common issues that might arise:
This might be due to file permission issues. Please read file permission issues chapter on how to detect and resolve the problem.
This is most likely due to a php error being thrown. Please enable the display_errors parameter in your
php.ini. Only with an error message the problem can be found.
Another way to check for PHP errors, is to have a look at your PHP error log. The PHP log shows information on errors and warnings thrown by PHP. Your host should have configured PHP to write that information to a log rather than output them on screen.
Please check this guide to PHP error messages for webdesigners for a more thorough view on the subject.