upgrade error (no replies)

#0 Piwik\Error::errorHandler(...) called at [/home/aisoft/public_html/piwik/core/Development.php:34]
#1 Piwik\Development::isEnabled(...) called at [/home/aisoft/public_html/piwik/core/Cache/PersistentCache.php:94]
#2 Piwik\Cache\PersistentCache::populateCache(...) called at [/home/aisoft/public_html/piwik/core/Cache/PersistentCache.php:49]
#3 Piwik\Cache\PersistentCache->__construct(...) called at [/home/aisoft/public_html/piwik/core/Plugin.php:141]
#4 Piwik\Plugin->__construct(...) called at [/home/aisoft/public_html/piwik/core/Plugin/Manager.php:870]
#5 Piwik\Plugin\Manager->makePluginClass(...) called at [/home/aisoft/public_html/piwik/core/Plugin/Manager.php:836]
#6 Piwik\Plugin\Manager->loadPlugin(...) called at [/home/aisoft/public_html/piwik/core/Plugin/Manager.php:776]
#7 Piwik\Plugin\Manager->reloadPlugins(...) called at [/home/aisoft/public_html/piwik/core/Plugin/Manager.php:615]
#8 Piwik\Plugin\Manager->loadPlugins(...) called at [/home/aisoft/public_html/piwik/core/Plugin/Manager.php:95]
#9 Piwik\Plugin\Manager->loadActivatedPlugins(...) called at [/home/aisoft/public_html/piwik/core/FrontController.php:323]
#10 Piwik\FrontController->init(...) called at [/home/aisoft/public_html/piwik/core/dispatch.php:33]
#11 require_once(...) called at [/home/aisoft/public_html/piwik/index.php:47]


after upgrading to v.2.5 i got this error and not able to run script.. please help me!