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[Serpius]

Check that your database prefix is correct in ./inc/config.php

hello, Please i have checked it ...what do i do in it 
I don't know what is missing and what to do

Here's a screenshot showing you how to do this.

Your database prefix will be different from what you see in the screenshot, but that is where you modify it to match your database prefix.

That is in the config.php file in the root/inc folder

You can disregard the 2nd part about changing the admin folder name.