Craft 3 not running on Ubuntu 18.04 I’ve set up a new Ubuntu 18.04 server, but can not get Craft 3 to run on it - despite it passing the Server test script with flying colours.

I know the server setup is OK as PHPmyAdmin is running on this server (though that has its own issues with PHP7.2, it does at least run).

I don’t want to use Composer as it is not the right choice for our use case; so I’ve downloaded the zip and used that. It won’t install via the browser as whenever I go to /admin/install it claims a 404 error (going to index.php?p=admin redirects to /admin/install).

If I go to the root of the site it claims an Internal Server Error. I can’t see any information in the /storage/logs files, nor in the /var/www/project/logs folder that Apache is configured to dump logs into when hitting the Internal Server Error. There are log entries - and I had issues with - permissions writing to files. Specifically to do with Yii2 file mutex and fopen.

Anyone got any pointers?

Apache is running as the default www-data user and group, the site files are owned by a user belonging to that group, and I’ve 774’d everything recursively.
When I had this problem previously, it was the permissions for the index.php that wasn't set to 644. 

Another issue I had once was my database password had some characters that wasn't accepted. Instead of getting errors, I just got a blank page saying Internal Server Error. Once I changed the password to omit weird characters, it worked perfectly. Wasted a ton of hours trying to figure that out.

Good luck!