How can I debug a 500 Internal Server error (IIS 8.5 Windows Server 2012 R2) where the fastcpi (php-cgi.exe) seems to crash once every few days
We have migrated a web site (WordPress/PHP/MySQL) from Ubuntu/Apache to WIndows/IIS 8.5 We are seeing 500 Internal Server Error once every couple of days - sometimes it happens at 8pm or 5am and it seems to fix itself within one hour. If we stop and start IIS the problem is fixed straight away. We are running PHP 7.0 on Windows Server 2012 R2 IIS 8.5 How can I figure out what is causing the FastCGI (php-cgi.exe) to fail?