Windows服务器中PHP错误报告的奇怪行为

I have successfully setup Php,Mysql and phpmyadmin in my windows server,but the problem occurs in error reporting.Here is the two cases of my problem.

CASE1

when i enable this line

error_reporting 
Production Value: E_ALL & ~E_DEPRECATED & ~E_STRICT

get all the errors of my Php script but the Phpmyadmin is crashed.it shows mbstring extension missing error.

CASE2

when i disable the above line Phpmyadmin works properly but didn't shows any error.

check your php.ini file in the root directory of your php installation. In the extensions part of the configuration you should find:

;extension=php_mbstring.dll

remove the leading ';'

 extension=php_mbstring.dll