Host (X) is blocked because of many connection errors.
Unblock with 'mysqladmin flush-hosts'.
You can change the max_connect_errors parameter of the server. The default value for max_connect_errors is 10. An example for changing it to 100:
> mysqld_safe --max_connect_errors = 100
This error message appears in mysql, when there are too many interrupted connections from host (X).
