everything was ok. but suddnley

[shahar_co]

Coppermine critical error:
Unable to connect to database !

MySQL said: Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (111)

[Nibbler]

That probably means mysql has stopped running on your server, wait and see if it comes back. Otherwise verify your database settings are correct in include/config.inc.php