I have the theory that it has to do something with SSL script for Https. I had https activated through my account but the new account doesn’t have it at the moment.
i just played around on a local installation with enforcing ssl and providing valid and invalid certificates - even without any certificate.
Besides the browsers warning the site showed up without any further problems.
perhaps the grav.log or httpd log would provide some more detailed information.
Thank you. The Server Error is about the “shortcode handler” or “shortcode core” plugin apparently. That’s what it says in the screenshot, no? Would it help to deactivate that plugin before transferring the whole webspace?