的解决方法：
官方的说法是：如果你升级mysql到4.1以上版本后遇到以上问题,请先确定你的mysql client 是4.1或者更高版本.(WINDOWS下有问题你就直接跳到下面看解决方法了,因为MYSQL 在WINDOWS是client和server一起装上了的)
请使用以下两种方法之一
其一:
mysql> SET PASSWORD FOR -> 'some_user'@'some_host' = OLD_PASSWORD('newpwd');其二:
mysql> UPDATE mysql.user SET Password = OLD_PASSWORD('newpwd') -> WHERE Host = 'some_host' AND User = 'some_user';mysql> FLUSH PRIVILEGES; 上面红色的部分请按自己实际情况修改.... 这样做后,连接就会正常了@! 英文说明： To solve this problem, you should use one of the following approaches: Upgrade all client programs to use a 4.1.1 or newer client library. When connecting to the server with a pre-4.1 client program, use an account that still has a pre-4.1-style password. Reset the password to pre-4.1 style for each user that needs to use a pre-4.1 client program. This can be done using the SET PASSWORD statement and the OLD_PASSWORD() function: mysql> SET PASSWORD FOR -> 'some_user'@'some_host' = OLD_PASSWORD('newpwd'); Alternatively, use UPDATE and FLUSH PRIVILEGES: mysql> UPDATE mysql.user SET Password = OLD_PASSWORD('newpwd') -> WHERE Host = 'some_host' AND User = 'some_user'; mysql> FLUSH PRIVILEGES; Substitute the password you want to use for ``newpwd'' in the preceding examples. MySQL cannot tell you what the original password was, so you'll need to pick a new one.