I can't connect to Mysql except reboot server

[passawut treesittichai]

Hello,

Information
Window server 2003
Plesk window 8.6.0.5

When have a problem mysql. I can't access to CP Plesk or Website have connect Mysql. It's show error below.

1. Error for CP Plesk
Warning: db_query() [function.db-query]: Couldn't fetch mysqli in E:\Program Files\Parallels\Plesk\admin\plib\common_func.php3 on line 229
ERROR: PleskMainDBException DB query failed: Unknown error 0: plib\common_func.php3:243 db_query(string 'set names utf8') 1: plib\common_func.php3:649 reconnect() 2: plib\common_func.php3:614 db_connect() 3: auto_prepend\auth.php3:80

2. Error for Website
Mysql does not connect

I get restart All service but It's not work.
I must reboot server only to be normal.

Please help me.
Thank you

 

[Satoriya]

When you notice the issue next time, check event viewer (Application and System) for the errors related to MySQL failure to understand the reasons.