mysql problem

[GandalfDDUK]

A client of our keeps getting the following error, and we need to sort it asap can someone please help;

Warning: mysql_connect(): Host 'server.domain.com' is blocked because of many connection errors. Unblock with 'mysqladmin flush-hosts' in /home/user/public_html/Connections/connPCRE.php on line 9

Fatal error: Host 'server.domain.com' is blocked because of many connection errors. Unblock with 'mysqladmin flush-hosts' in /home/user/public_html/Connections/connPCRE.php on line 9

[TristanToxic]

You already gave the answer yourself:

mysqladmin flush-hosts

(or mysqladmin -u <user> -p <pass> flush-hosts)