MySQL Database plugin ' federated ' is disabled. Error resolution

The exact contents of the error are:

121012 11:35:03 [note] Plugin ' federated ' is disabled.
121012 11:35:03 InnoDB:Error:unable to create temporary file; Errno:2
121012 11:35:03 [ERROR] Plugin ' InnoDB ' init function returned ERROR.
121012 11:35:03 [ERROR] Plugin ' InnoDB ' registration as a STORAGE ENGINE.
121012 11:35:03 [ERROR] unknown/unsupported table Type:innodb
121012 11:35:03 [ERROR] Aborting

I find solutions on the Internet:

1, in the My.ini file in [mysqld] add a row tmpdir= "d:/mysql/data/" modified, or can not start or could start but shutdown after the same problem, and then I did a second step, restart normal.

2, delete the data directory in addition to the database folder other files, restart MySQL, problem solving.

I did it the way I did, but no, I figured out a solution that was similar to the above.

First step:

Just delete the Ib_logfile0 and ib_logfile1 two files in the MySQL directory
Step Two:

Found the reason for the failure to start: MySQL does not automatically initialize the Tmpdir (temporary file directory) at the time of installation, so to add the Tmpdir path in the configuration file My.ini.

Finally, add in My.ini:

[Mysqld]
#自己指定的临时文件目录
Tmpdir= "E:/program files/mysql/mysql Server 5.1/temp/"