title: Could not start MySQL server in WAMP
body: <p>I installed WAMP server locally on my machine and got it up and working for my web site. All of a sudden, I saw that the MYSQL service was not starting (I suppose some data corruption?) and found the log below. </p>
  
  <p>Any idea on how to solve?</p>
  
  <pre><code>2017-02-28T05:38:10.517960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.    
  2017-02-28T05:38:10.517960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\engine_cost.ibd' OS error: 71
  2017-02-28T05:38:10.522960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/engine_cost`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.522960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/engine_cost` because it could not be opened.
  2017-02-28T05:38:10.562960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.562960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\gtid_executed.ibd' OS error: 71
  2017-02-28T05:38:10.562960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/gtid_executed`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.567960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/gtid_executed` because it could not be opened.
  2017-02-28T05:38:10.567960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.572960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\help_category.ibd' OS error: 71
  2017-02-28T05:38:10.572960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/help_category`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.572960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/help_category` because it could not be opened.
  2017-02-28T05:38:10.577960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.577960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\help_keyword.ibd' OS error: 71
  2017-02-28T05:38:10.577960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/help_keyword`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.582960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/help_keyword` because it could not be opened.
  2017-02-28T05:38:10.582960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.582960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\help_relation.ibd' OS error: 71
  2017-02-28T05:38:10.587960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/help_relation`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.587960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/help_relation` because it could not be opened.
  2017-02-28T05:38:10.592960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.592960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\help_topic.ibd' OS error: 71
  2017-02-28T05:38:10.592960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/help_topic`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.597960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/help_topic` because it could not be opened.
  2017-02-28T05:38:10.597960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.602960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\innodb_index_stats.ibd' OS error: 71
  2017-02-28T05:38:10.602960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/innodb_index_stats`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.602960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/innodb_index_stats` because it could not be opened.
  2017-02-28T05:38:10.607960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.607960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\innodb_table_stats.ibd' OS error: 71
  2017-02-28T05:38:10.612960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/innodb_table_stats`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.612960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/innodb_table_stats` because it could not be opened.
  2017-02-28T05:38:10.702960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.707960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\plugin.ibd' OS error: 71
  2017-02-28T05:38:10.707960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/plugin`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.712960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/plugin` because it could not be opened.
  2017-02-28T05:38:10.777960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.777960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\server_cost.ibd' OS error: 71
  2017-02-28T05:38:10.777960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/server_cost`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.782960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/server_cost` because it could not be opened.
  2017-02-28T05:38:10.782960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.782960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\servers.ibd' OS error: 71
  2017-02-28T05:38:10.787960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/servers`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.787960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/servers` because it could not be opened.
  2017-02-28T05:38:10.792960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.792960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\slave_master_info.ibd' OS error: 71
  2017-02-28T05:38:10.792960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/slave_master_info`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.792960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/slave_master_info` because it could not be opened.
  2017-02-28T05:38:10.797960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.797960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\slave_relay_log_info.ibd' OS error: 71
  2017-02-28T05:38:10.797960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/slave_relay_log_info`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.802960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/slave_relay_log_info` because it could not be opened.
  2017-02-28T05:38:10.802960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.807960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\slave_worker_info.ibd' OS error: 71
  2017-02-28T05:38:10.807960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/slave_worker_info`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.807960Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/slave_worker_info` because it could not be opened.
  2017-02-28T05:38:10.842960Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.842960Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\time_zone.ibd' OS error: 71
  2017-02-28T05:38:10.842960Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/time_zone`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.847961Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/time_zone` because it could not be opened.
  2017-02-28T05:38:10.847961Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.852961Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\time_zone_leap_second.ibd' OS error: 71
  2017-02-28T05:38:10.852961Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/time_zone_leap_second`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.852961Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/time_zone_leap_second` because it could not be opened.
  2017-02-28T05:38:10.857961Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.857961Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\time_zone_name.ibd' OS error: 71
  2017-02-28T05:38:10.857961Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/time_zone_name`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.862961Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/time_zone_name` because it could not be opened.
  2017-02-28T05:38:10.867961Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.867961Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\time_zone_transition.ibd' OS error: 71
  2017-02-28T05:38:10.867961Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/time_zone_transition`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.872961Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/time_zone_transition` because it could not be opened.
  2017-02-28T05:38:10.872961Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.877961Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\time_zone_transition_type.ibd' OS error: 71
  2017-02-28T05:38:10.877961Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/time_zone_transition_type`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.882961Z 0 [Warning] InnoDB: Ignoring tablespace `mysql/time_zone_transition_type` because it could not be opened.
  2017-02-28T05:38:10.972961Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:10.972961Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\sys\sys_config.ibd' OS error: 71
  2017-02-28T05:38:10.977961Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `sys/sys_config`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:10.982961Z 0 [Warning] InnoDB: Ignoring tablespace `sys/sys_config` because it could not be opened.
  2017-02-28T05:38:11.937962Z 0 [ERROR] InnoDB: Failed to find tablespace for table `mysql`.`innodb_index_stats` in the cache. Attempting to load the tablespace with space id 14
  wampmysqld: Table 'mysql.plugin' doesn't exist
  2017-02-28T05:38:11.937962Z 0 [ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.
  2017-02-28T05:38:11.942962Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:11.942962Z 0 [Warning] Gtid table is not ready to be used. Table 'mysql.gtid_executed' cannot be opened.
  2017-02-28T05:38:11.947962Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\innodb_index_stats.ibd' OS error: 71
  2017-02-28T05:38:11.952962Z 0 [Warning] Failed to open optimizer cost constant tables
  2017-02-28T05:38:11.957962Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/innodb_index_stats`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:11.957962Z 0 [ERROR] InnoDB: Failed to find tablespace for table `mysql`.`innodb_table_stats` in the cache. Attempting to load the tablespace with space id 13
  2017-02-28T05:38:12.172962Z 0 [ERROR] InnoDB: Operating system error number 2 in a file operation.
  2017-02-28T05:38:12.212962Z 0 [ERROR] InnoDB: Cannot open datafile for read-only: '.\mysql\innodb_table_stats.ibd' OS error: 71
  2017-02-28T05:38:12.257962Z 0 [ERROR] InnoDB: Could not find a valid tablespace file for `mysql/innodb_table_stats`. Please refer to http://dev.mysql.com/doc/refman/5.7/en/innodb-troubleshooting-datadict.html for how to resolve the issue.
  2017-02-28T05:38:16.465970Z 0 [ERROR] Fatal error: Can't open and lock privilege tables: Table 'mysql.user' doesn't exist
  2017-02-28T05:38:16.500970Z 0 [ERROR] Aborting
  </code></pre>