I have seen several posts on this error, but have not seen a resolution as yet. I installed XAMPP 1.8.3 four days ago and created a MySQL DB (v5.6.11) . I successfully started MySQL and accessed the DB more than once that same day. Three days later MySQL fails on startup.
Message seen on the XAMPP v3.2.1 control panel -
10:32:17 AM [mysql] Error: MySQL shutdown unexpectedly.
10:32:17 AM [mysql] This may be due to a blocked port, missing dependencies,
10:32:17 AM [mysql] improper privileges, a crash, or a shutdown by another method.
10:32:17 AM [mysql] Press the Logs button to view error logs and check
10:32:17 AM [mysql] the Windows Event Viewer for more clues
10:32:17 AM [mysql] If you need more help, copy and post this
10:32:17 AM [mysql] entire log window on the forums
Errors logged in MySQL_error -
2013-09-10 10:32:17 4516 [Note] Plugin 'FEDERATED' is disabled.
2013-09-10 10:32:17 136c 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.
2013-09-10 10:32:17 4516 [Note] InnoDB: The InnoDB memory heap is disabled
2013-09-10 10:32:17 4516 [Note] InnoDB: Mutexes and rw_locks use Windows interlocked functions
2013-09-10 10:32:17 4516 [Note] InnoDB: Compressed tables use zlib 1.2.3
2013-09-10 10:32:17 4516 [Note] InnoDB: Not using CPU crc32 instructions
2013-09-10 10:32:17 4516 [Note] InnoDB: Initializing buffer pool, size = 16.0M
2013-09-10 10:32:17 4516 [Note] InnoDB: Completed initialization of buffer pool
2013-09-10 10:32:17 4516 [Note] InnoDB: Highest supported file format is Barracuda.
2013-09-10 10:32:17 4516 [Note] InnoDB: The log sequence numbers 0 and 0 in ibdata files do not match the log sequence number 2830196 in the ib_logfiles!
2013-09-10 10:32:17 4516 [Note] InnoDB: Database was not shutdown normally!
2013-09-10 10:32:17 4516 [Note] InnoDB: Starting crash recovery.
2013-09-10 10:32:17 4516 [Note] InnoDB: Reading tablespace information from the .ibd files...
2013-09-10 10:32:17 4516 [ERROR] InnoDB: Attempted to open a previously opened tablespace. Previous tablespace mysql/slave_relay_log_info uses space ID: 3 at filepath: .\mysql\slave_relay_log_info.ibd. Cannot open tablespace wordpress/wp_terms which uses space ID: 3 at filepath: .\wordpress\wp_terms.ibd
InnoDB: Error: could not open single-table tablespace file .\wordpress\wp_terms.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.
I have tried one of the solutions offered which was to remove the referenced tablespace, but it just then fails on a different tablespace.
On my earlier use of MySQL I shut it down using the XAMPP control panel, which I assume is an appropriate method for shutting down MySQL and Apache.
I have no data to lose, so a reinstall (different version?) is not an issue if that is the solution.
My apologies if a resolution has previously been posted, but I could not find one. Thank you for your kind attention.