Cannot access subdirectory subpages

by

Finally fixed this errow after browsing for a couple of hours and trying many options.

In this block in your Apache httpd.conf file,
(located in my CentOS instance at $ sudo vi /etc/httpd/conf/httpd.conf)

#
# AllowOverride controls what directives may be placed in .htaccess files.
# It can be "All", "None", or any combination of the keywords:
#   Options FileInfo AuthConfig Limit
#
    AllowOverride None

change AllowOverride None to AllowOverride All.

Src: https://wordpress.org/support/topic/secondary-or-child-pages-returning-a-404-error-after-wp-34-update#post-3830892