I updated PHP version to 7.1.29 and received the error – “The site is experiencing technical difficulties. Please check your site admin email inbox for instructions.” I reverted back to 7.0.33 and website worked properly, so I changed it back to 7.1 and renamed the plugins folder to see if it was a plugin issue. I discovered it was the Revolution Slider plugin – The current version I am using is this 5.0.4.1. Hope this helps diagnose the problem!