Magento – error : cache_dir must be a directory

cacheerrormagento-1.7

I am working with Magento 1.7 and suddenly I have this error when I go to cache management:

cache_dir must be a directory

I tried this solution to change this file lib/Zend/Cache/Backend/File.php

'cache_dir' => 'null' to 'cache_dir' => 'tmp/' but does not work

Go to location lib/Zend/Cache/Backend/ and open file.php and change: null to NULL

See:

protected $_options = array(
    'cache_dir' => NULL,
    'file_locking' => true,

Try this

Create a new directory called tmp

Navigate to app/code/core/Zend/Cache/Backend/

Edit File.php

Change:

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

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

This error is not Magento-specific. It relates to Zend Cache.

Set sys_temp_dir in php.ini to a path that can be reached by IUSR then restart IIS to apply changes.