How can I solve "Error: MySQL shutdown unexpectedly"?
mysql, xampp
Solution
Important: do not delete the `ibdata1` file. You could destroy all your databases.
Instead, first try using the MySQL backup folder which is included with XAMPP. So do next steps:
- Rename folder `mysql/data` to `mysql/data_old`
- Make a copy of `mysql/backup` folder and name it as `mysql/data`
- Copy all your database folders from `mysql/data_old` into `mysql/data` (except `mysql`, `performance_schema`, and `phpmyadmin` folders)
- Copy `mysql/data_old/ibdata1` file into `mysql/data` folder
- Start MySQL from XAMPP control panel
And, voilà!
As mentioned by some users, this is an emergency solution, not a permanent one. After recovering your data is strongly recommended to back it up, and reinstalling XAMPP, because the failure is related to a malfunction from some of the files of XAMPP, not the databases.
Problem
When I open XAMPP and click the start MySQL button, it gives me an error. I had started it just before, but now it isn't working. 12:19:12 PM [mysql] Attempting to start MySQL app... 12:19:12 PM [mysql] Status change detected: running 12:19:13 PM [mysql] Status change detected: stopped 12:19:13 PM [mysql] Error: MySQL shutdown unexpectedly. 12:19:13 PM [mysql] This may be due to a blocked port, missing dependencies, 12:19:13 PM [mysql] improper privileges, a crash, or a shutdown by another method 12:19:13 PM [mysql] Press the Logs button to view error logs and check 12:19:13 PM [mysql] the Windows Event Viewer for more clues 12:19:13 PM [mysql] If you need more help, copy and post this 12:19:13 PM [mysql] entire log window on the forums Here is the contents of the error log: 2013-08-02 12:19:12 4536 [Note] Plugin 'FEDERATED' is disabled. 2013-08-02 12:19:12 f64 InnoDB: Warning: Using innodb_additional_mem_pool_size is DEPRECATED. This option may be removed in future releases, together with the option innodb_use_sys_malloc and with the InnoDB's internal memory allocator. 2013-08-02 12:19:12 4536 [Note] InnoDB: The InnoDB memory heap is disabled 2013-08-02 12:19:12 4536 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions 2013-08-02 12:19:12 4536 [Note] InnoDB: Compressed tables use zlib 1.2.3 2013-08-02 12:19:12 4536 [Note] InnoDB: Not using CPU crc32 instructions 2013-08-02 12:19:12 4536 [Note] InnoDB: Initializing buffer pool, size = 16.0M 2013-08-02 12:19:12 4536 [Note] InnoDB: Completed initialization of buffer pool 2013-08-02 12:19:12 4536 [Note] InnoDB: Highest supported file format is Barracuda. 2013-08-02 12:19:12 4536 [Note] InnoDB: The log sequence numbers 0 and 0 in ibdata files do not match the log sequence number 1616798 in the ib_logfiles! 2013-08-02 12:19:12 4536 [Note] InnoDB: Database was not shutdown normally! 2013-08-02 12:19:12 4536 [Note] InnoDB: Starting crash recovery. 2013-08-02 12:19:12 4536 [Note] InnoDB: Reading tablespace information from the .ibd files... The most important error message is here: 2013-08-02 12:19:12 4536 [ERROR] InnoDB: Attempted to open a previously opened tablespace. Previous tablespace mysql/innodb_table_stats uses space ID: 1 at filepath: .\mysql\innodb_table_stats.ibd. Cannot open tablespace xat/payments which uses space ID: 1 at filepath: .\xat\payments.ibd The rest of the log: InnoDB: Error: could not open single-table tablespace file .\xat\payments.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. What is the cause of these errors and how can I rectify them?