mysqli_error() error in home page WCP

Hi everybody,
I have installed WCP but in header of homepage, I got this error:
Warning: mysqli_query() expects parameter 1 to be mysqli, boolean given in /usr/local/cwpsrv/htdocs/resources/admin/include/functions/func_mysql.php on line 0

Warning: mysqli_error() expects exactly 1 parameter, 0 given in /usr/local/cwpsrv/htdocs/resources/admin/include/functions/func_mysql.php on line 0

Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, null given in /usr/local/cwpsrv/htdocs/resources/admin/include/functions/func_mysql.php on line 0

Warning: mysqli_free_result() expects parameter 1 to be mysqli_result, null given in /usr/local/cwpsrv/htdocs/resources/admin/include/functions/func_mysql.php on line 0
Please help me
Thank you very much!

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