For computers from the early to mid 2010s in particular, the wifi card might be reported as not fitted or working. try these steps.
Reset the SMC Reset the PRAM Remove the file: /etc/sysctl.conf The problem might be wifi/Bluetooth cable, it runs over the disc drive and is prone to failure.
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Warning: mysqli_connect(): Error while reading greeting packet. PID=90651 in /Library/WebServer/Documents/Owen2/Inc/Footer.inc.php on line 35
Warning: mysqli_connect(): (HY000/2006): MySQL server has gone away in /Library/WebServer/Documents/Owen2/Inc/Footer.inc.php on line 35
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Could not connect to MySQL: