日志如下：

2017-09-01 09:24:57 1996 [Note] Plugin ‘FEDERATED’ is disabled.
2017-09-01 09:24:57 1996 [Note] InnoDB: The InnoDB memory heap is disabled
2017-09-01 09:24:57 1996 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions
2017-09-01 09:24:57 1996 [Note] InnoDB: Compressed tables use zlib 1.2.3
2017-09-01 09:24:57 1996 [Note] InnoDB: Not using CPU crc32 instructions
2017-09-01 09:24:57 1996 [Note] InnoDB: Initializing buffer pool, size = 128.0M
2017-09-01 09:24:57 1996 [Note] InnoDB: Completed initialization of buffer pool
2017-09-01 09:24:57 1996 [Note] InnoDB: Highest supported file format is Barracuda.
2017-09-01 09:24:57 1996 [Note] InnoDB: The log sequence numbers 1602631 and 1602631 in ibdata files do not match the log sequence number 2188207 in the ib_logfiles!
2017-09-01 09:24:57 1996 [Note] InnoDB: Database was not shutdown normally!
2017-09-01 09:24:57 1996 [Note] InnoDB: Starting crash recovery.
2017-09-01 09:24:57 1996 [Note] InnoDB: Reading tablespace information from the .ibd files…
2017-09-01 09:24:57 1996 [ERROR] InnoDB: Attempted to open a previously opened tablespace. Previous tablespace hmail/cache uses space ID: 42 at filepath: .\hmail\cache.ibd. Cannot open tablespace mail/cache which uses space ID: 42 at filepath: .\mail\cache.ibd
2017-09-01 09:24:57 1784 InnoDB: Operating system error number 997 in a file operation.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.6/en/operating-system-error-codes.html
InnoDB: Error: could not open single-table tablespace file .\mail\cache.ibd
InnoDB: We do not continue the crash recovery, because the table may become
InnoDB: corrupt if we cannot apply the log records in the InnoDB log to it.
InnoDB: To fix the problem and start mysqld:
InnoDB: 1) If there is a permission problem in the file and mysqld cannot
InnoDB: open the file, you should modify the permissions.
InnoDB: 2) If the table is not needed, or you can restore it from a backup,
InnoDB: then you can remove the .ibd file, and InnoDB will do a normal
InnoDB: crash recovery and ignore that table.
InnoDB: 3) If the file system or the disk is broken, and you cannot remove
InnoDB: the .ibd file, you can set innodb_force_recovery > 0 in my.cnf
InnoDB: and force InnoDB to continue crash recovery here.

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 把D:\wamp\bin\mysql\mysql5.6.12\data 目录下的 ib_logfile0和ib_logfile1 重新命名或者删除，重启启动mysql服务，服务正常启动。

系统会重新生成这两个文件。