Solution to AH01630 error: client denied by server configuration on Apache 2.4.

It turns out that with the update to Apache 2.4 some of your sites may stop working due to a change in the Authorization used in the mod_authz_dbm module. If you've made it this far, you probably received an error like this:
[authz_core:error] [pid 15479] [client 127.0.0.1:37968] AH01630: client denied by server configuration: /var/www/yourwebsite.com
And this did not happen in Apache 2.2 because you probably had a configuration like the following on your site:
Order allow,deny
Allow from all
In version 2.4, the equivalent of this configuration would be:
Require all granted
If you don't know where to find Apache's configuration on your machine, we invite you to check out our article Where are the Apache configuration files saved?.
Both configurations can coexist, so it is recommended that you leave both forms so that your site can work with both versions of Apache. On the other hand, if you want to do the opposite, that is, something like this:
Order deny,allow
Deny from all
You must configure the equivalent in Apache 2.4 as follows:
Require all denied