Getting an error

I have just finished installing Nextcloud via the Snap method. When I try to access my Nextcloud via Chromium I get the following error

The server was unable to complete your request.
If this happens again, please send the technical details below to the server administrator.
More details can be found in the server log.

Technical details

  • Remote Address:
  • Request ID: RUqslBAOB86vURIDVE2E

I have 2 questions

  1. what is the problem?
  2. Where is the error.log file?

BTW - I tried to install nextcloud manually but ran into other problems so I stopped apache, tossed the nextcloud folder (/var/www/html/nextcloud), removed the config stuff for nextcloud in /etc/apache2, and purged apache. I then re-installed apache2 and verified that it worked. I then installed nextcloud via snap. It gives me the above error when I try to access http://localhost/nextcloud - I was expecting some kind of login/registration page.

Iā€™m running apache2 V 2.4.29 on Ubuntu 18.04