Randy Sandberg on "missing the MySQL extension"

P.S., On a brand new install of WordPress using MAMP ver. 3.5 on my MacBook Air, when I run my phpinfo.php file, I see:

Loaded Configuration File	/Applications/MAMP/bin/php/php7.0.0/conf/php.ini
Scan this dir for additional .ini files	(none)
Additional .ini files parsed	(none)

Thus, once you run the phpinfo.php file on your server, you'll know which php.ini is loaded. Then you can remove it from your WordPress directory and run the phpinfo.php file again to find the default php.ini file. Which in my case, is HUGE! :-)