Here is a known error which can occur when installing Magento:

Here is the solution:

1. Navigate to the “errors” folder.
2. Change local.xml.sample to local.xml
3. You should now see a new list of crazy errors all over the Magento page – this is okay.
4. Open magento/lib/Zend/Cache/Backend/File.php and look for:
   
   protected $_options = array( 'cache_dir' => 'null',

   1 2	protected $_options = array( 'cache_dir' => 'null',

   
    
5. Change it to:
   
   protected $_options = array( 'cache_dir' => 'tmp/',

   1 2	protected $_options = array( 'cache_dir' => 'tmp/',

   
    
6. Save it
7. Now the final step is to go create a tmp folder in the root Magento folder.
8. That’s it.

http://support.hostgator.in/articles/specialized-help/technical/magento-install-error-exception-printing-is-disabled