Owncloud not available after installation on Ubuntu server 14.04

This is because Apache 2.4's default web root is /var/www/html as opposed to /var/www. ownCloud's default installation ends up in /var/www/owncloud, which is outside of the web root.

I first solved this by creating a symbolic link at /var/www/html/owncloud, but I found it cleaner to simply change Apache's document root to /var/www/owncloud. If you want to preserve the owncloud subdirectory, you can point it to /var/www and get rid of /var/www/html and its contents.

Edit /etc/apache2/sites-enabled/000-default.conf (and/or the appropriate configuration for the SSL site in the same location, depending on your setup) to point DocumentRoot to /var/www or /var/www/owncloud, whichever works for you.

I just figured this out myself, so it may warrant further configuration changes. I will update this post if/when I figure out more tweaks need to be made, but it seems to be working for me, anyway.

Also this has nothing to do with programming and really belongs on superuser.com or perhaps serverfault.com.

This would be more appropriate as a comment as I'm completely clueless as to the solution, but the strange system of SO doesn't allow me to post comments. I have an idea that may not help but just want to confirm that it's not the problem.

Have you tried the following URL?

http://localhost/owncloud/index.html

The first thing that came to mind is that there is a problem with your Default Document settings.

If the above works, you can fix it so you don't have to define the HTML file in the URL by creating a .htaccess file in your server root directory with the contents being:

DirectoryIndex  index.php index.html index.htm default.html default.htm home.html

Hope this helps.