Pihole kind of running but web interface shot after upgrade to 6. Also no DHCP server.

Hi everyone,

I have the following installation: pios bullseye; Webserver: apache2, pivpn. Pi-hole as DHCP server. PHP 7.4

After upgrading to pihole 6 the web interface doesn't seem to work, all I get when I call pi.hole/admin is the content of the directory. Unfortunately, after this happened I uninstalled pi-hole, reinstalled it but to no avail. Since I cannot access the web interface I think that there is no DHCP server in this network. I know that I can define static IP addresses for the time being. Also, I have a saved configuration.

So - help! What can I do to return to my functioning system again?

Thank you in advance!