I have been getting ERROR: Site [such] does not exist! when running
sudo a2dissite "some virtual host"You probably updated your server installation and one of the updates included the upgrade of Apache to version 2.4.x
In Apache 2.4.x the virtual host configuration files, located in the /etc/apache2/sites-available/ directory, must have the .conf extension.
so use line below to solve this issue and you will be good to go
mv /etc/apache2/sites-available/some_site /etc/apache2/sites-available/some_site.conf