PHPMYADMIN is showing raw code, no excecution of php

I’ve found heaps of similar issues online, but none of the recommendations helped (install libapache2-mod-php7.0, php-mbstring, php-gettext etc.). I’ve removed php7.0, mysql server, phpmyadmin etc and reinstalled it.
I have no idea anymore. I’m trying since days to get that fixed. I’m already considering to cancel the whole project … :frowning:

My setup:
ubuntu 16.04.01 LTS
PHP 7.0

Thanks in advance, help much appreciated…

Anyone an idea…?

I have the suspicion it’s not working because the quotas are not enabled, which is not possible. I’ll get the error: Failed to turn on quotas : quotaon: using //aquota.user on /dev/vda1 [/]: No such process quotaon: Quota format not supported in kernel.
I’ve found an old thread which relates obviously to the same issue: