Laravel 4 : UnexpectedValueException (The stream or file LOG_FILE could not be opened: failed to open stream: No such file or directory)

The stream or file "PROJECT_ROOT/app/storage/logs/LARALVEL_LOG_FILE" could not be opened: failed to open stream: No such file or directory

This may happen when laravel can' find log file.
One solution is to create logs dir manually :

1. #Goto your laravel project dir. Do the following on terminal:
2. mkdir app/storage/logs
3. 
   
4. #incase you forgot file permissions
5. chmod -R 777 app/