MySQL does not start when upgrading OSX to Yosemite or El Capitan

Question

I know similar questions exist, such as MySQL with MAMP does not work with OSX Yosemite 10.10. However, I do have MAMP, nor XAMPP installed on my computer.

When I tr

Answer 1

The .pid is the processid of the running mysql server instance. It appears in the data folder when mysql is running and removes itself when mysql is shutdown.

If the OSX operating system is upgraded and mysql is not shutdown properly before the upgrade,mysql quits when it started up it just quits because of the .pid file.

There are a few tricks you can try, http://coolestguidesontheplanet.com/mysql-error-server-quit-without-updating-pid-file/ failing these a reinstall is needed.