I recently purchased the theme “Polyclinic”. After installation I activated the theme to get an HTTP Error 500. It took me a bit to ftp in and remove the Polyclinic theme and restore our site, after that I read up on the support page and did the exact steps the creator specified. I still was getting the HTTP Error 500 message. I then thought it was a plugin issue so I deactivated all our existing plugins and tried again. Still received the HTTP Error 500 message. I have WordPress version 5.0.3 installed. I have checked the forums and tried the normal recommended troubleshooting steps for the HTTP Error 500 message, none have worked.