Host 'opc9.fastmag.fr' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

Host 'opc9.fastmag.fr' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

Run-time error:
SQLFIRST: Impossible d'effectuer cette opération sur un ensemble de données fermé at address 13760