Mysql 5.5.25 must be restarted to connect
Please keep in mind what the MySQL Documentation says about max_connect_errors

If more than this many successive connection requests from a host are interrupted without a successful connection, the server blocks that host from further connections. You can unblock blocked hosts by flushing the host cache. To do so, issue a FLUSH HOSTS statement or execute a mysqladmin flush-hosts command. If a connection is established successfully within fewer than max_connect_errors attempts after a previous connection was interrupted, the error count for the host is cleared to zero. However, once a host is blocked, flushing the host cache is the only way to unblock it.

MySQL 5.5's default value for max_connect_errors is 10.
I have two suggestions on resetting the connection error count errors besides restarting mysql:
SUGGESTION #1
Create a one line SQL script (such as C:\FlushHosts.sql)
Setup a scheduled task to execute mysql -uroot &lt; C:\FlushHosts.sql every hour
SUGGESTION #2
Goto my.ini and add the following line
[mysqld]
max_connect_errors=18446744073709547520

Then, login to mysql client and run this:
mysql&gt; SET GLOBAL max_connect_errors = 18446744073709547520;

After setting max_connect_errors this high, you should never get connection errors. Otherwise, you must running mysql in some parallel universe.
Give it a Try !!!