I've tried every post about this problem on Stack Exchange. None have worked.
I started with OS X El Capitan and had similar issues Upgraded to Sierra thinking it might help....oops. I have tried reinstalling using the DMG from MySQL. I have tried changing permissions according to directions on other StackExchange posts. I have tried killing running instances of MySQL. I have tried changing ownership of files according to directions on other StackExchange posts. I have tried installing with HomeBrew. I have tried installing older versions of MySQL. I have tried creating pid and conf files by hand. I have tried deleting .err files in the data directory.
Nothing has seemed to work for me.
Attempting to start a fresh install of MySQL 5.7 on OS X Sierra 10.12 yields the following results:
~ /usr/local/mysql/support-files/mysql.server start
Starting MySQL
./usr/local/mysql/bin/mysqld_safe: line 133: /usr/local/mysql/data/Scotts-MacBook-Pro.local.err: Permission denied
/usr/local/mysql/bin/mysqld_safe: line 133: /usr/local/mysql/data/Scotts-MacBook-Pro.local.err: Permission denied
/usr/local/mysql/bin/mysqld_safe: line 178: /usr/local/mysql/data/Scotts-MacBook-Pro.local.err: Permission denied
/usr/local/mysql/bin/mysqld_safe: line 133: /usr/local/mysql/data/Scotts-MacBook-Pro.local.err: Permission denied
ERROR! The server quit without updating PID file (/usr/local/mysql/data/Scotts-MacBook-Pro.local.pid).
Any ideas?