Error 500 after upgrading locally from 1.0.9 to the latest (2.3.1)

Hello, I’m working on upgrading a client’s site that’s currently on 1.0.9. I followed the directions at on how to upgrade from Kirby 1, but I’m now getting a 500 error. It’s not an .htaccess issue I don’t think, as I verified it’s getting loaded. Any ideas?

Are you running your site in a subfolder?

Have you tried to set the RewriteBase in your .htaccess?

Have you made sure that your PHP Version is at least 5.4, better 5.6 or ideally 7?

Yes, I’ve set the RewriteBase, and I’m running PHP 5.6.

Yes, I’m running the site in a subfolder.

Is there anything in your PHP error log?

Nope, nothing in my php error logs related to this.

What happens if you rename the .htaccess file so that it doesn’t apply anymore? You should then be able to view the homepage of your site.

Additional context: when I downgrade back to 1.0.9, it works fine.

Does a fresh 2.3.1 starterkit run in your environment?

Yes, just tested — a fresh install in the same environment works fine with zero config.

Do you happen to have any leftovers from 1.0.9 in your config.php?

Are your sure that all files from 1.0.9 were properly replaced?

In your updated old install look if you find a file like /site/blueprints/site.yml or /site/blueprints/site.php.

If not copy this file from a fresh Kirby 2.3.1 download to this place.

Good luck!

Could you pls. explain why and how that would cause a 500 error on the frontend?