Ensure that the Apache user has the required access permissions to the apache-install-location/conf/ directory and files in this directory. The Apache user is the UNIX user under which the Apache server responds to requests. This user is defined in the file httpd.conf. If you installed Apache as a root user, read the note about configuring the Apache user and group in apache-install-location/conf/httpd.conf.
Ensure that your configuration of users and groups meets the security requirements for this directory. For example, to restrict access to this directory, add the Apache user to the same user group as the owner of the directory.