win2012+IIS8.5+PHP7.12+MYSQL5.7.17+DZ3.3全新安装错误

win2012+IIS8.5+PHP7.12+MYSQL5.7.17+DZ3.3全新安装错误
Discuz! Database Error(0) notconnect
PHP Debug

No.	File	Line	Code
1	index.php	130	require(%s)
2	forum.php	56	discuz_application->init()
3	source/class/discuz/discuz_application.php	65	discuz_application->_init_db()
4	source/class/discuz/discuz_application.php	400	discuz_database::init(%s, Array)
5	source/class/discuz/discuz_database.php	23	db_driver_mysqli->connect()
6	source/class/db/db_driver_mysqli.php	74	db_driver_mysqli->_dbconnect(%s, %s, %s, %s, %s, %s)
7	source/class/db/db_driver_mysqli.php	84	db_driver_mysqli->halt(%s, %d)
8	source/class/db/db_driver_mysqli.php	222	break()

:'(:'(人气这样子的差啊

mysql 无法连接？