Hello,
most likely there is some extension that needs a specific version of PHP.
Please get inside the Global Configuration page and set Error Reporting to Development and turn the Debug mode on.
You should get a more detailed error, telling you which file is causing the error.
If you still don't get any specific file, you should take a look at your error log file inside your host control panel. In that case you should ask your hosting where you can find it.
Davide Tampellini
Developer and Support Staff
🇮🇹Italian: native 🇬🇧English: good • 🕐 My time zone is Europe / Rome (UTC +1)
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!