Yii user management error at install

I have been trying to install yii-user management module in freebsd system but when I type in my browser the url to install the yii user management I get the following error:

The table "{{users}}" for active record class "YumUser" cannot be found in the database.

I try fixing it by adding ‘tablePrefix’=>’’ in the mysql database array in main.php

but I still get the error. I dowload the yii-user-management version 0.8rc3.tar. How do I fix this error? I am new to yii.