A Yii2 App Failed to Start

Hi! I have experienced a strange behavior when tried to start my App. Trying to run it results into the following:

 PHP Warning – yii\base\ErrorException

mb_strlen() expects parameter 1 to be string, array given


On your Windows system with PHP and Apache, you have to modify the PHP.INI file so that includes the following line:


(inside the main [PHP] section) and restart Apache. After that, the call to mb_strlen succeeded.

Thanks a lot,chandran for your reply. I am using a debian based distribution (Kali Linux). I wrote the app 3 months ago, it was running well but I didn’t touch anything related to the app since that time.

Solution Found!

"php composer.phar update" solved my problem