How to resolve ???
I has changed in vendor\magento\zendframework1\library\Zend\Cache\Backend\File.php:99
Change 'cache_dir' => null to 'cache_dir' => 'var/cache'. And not resolve this.
Plsssss help me !!! Thank Alls :D
Check your var/log/exception.log - It should throw an error if it cannot access the var/cache directory. You may need to the full absolute URL. In my case it was something like:
'cache_dir' => 'C:/websites/domainname.com/something/var/cache'
Please note this is not a good permanent solution as it modifies core files, and may cause issues later. It's better to override the file if possible.
