Warning: DocumentRoot x does not exist when starting apache2

The recommended way to enable and disable Apache websites is using the a2ensite and a2dissite (short for Apache 2 Enable/Disable Site).

What these two tools do is basically adding/removing links to/from /etc/apache2/sites-enabled. Such links point to /etc/apache2/sites-available.

Because you have removed the files, I'd recommend not just disabling the sites (i.e. removing the links from sites-enabled), but also remove the site configurations all toghether (i.e. removing both the links from sites-enabled and the files from sites-available).

In short, you should:

1. Find the sites of which you have removed the files: ls /etc/apache2/sites-enabled
2. Disable such sites: rm /etc/apache2/sites-enabled/site1 /etc/apache2/sites-enabled/site2
3. (Optional) totally remove the configuration files for such sites: rm /etc/apache2/sites-available/site1 /etc/apache2/sites-available/site2

Hard to tell with what little configuration information you posted.

You need to check your Apache configuration files and virtual hosts. If you are no longer using /var/www/PATH/TO/DIRECTORY/ , disable the virtual host that is using that directory and/or update your apache configuration.

See:

https://help.ubuntu.com/community/ApacheMySQLPHP

https://help.ubuntu.com/12.04/serverguide/httpd.html

If that does not solve the problem, please update your question and provide additional configuration information.