It’s unlikely that you need to allow all IP addresses access to phpMyAdmin. Instead it is more secure to whitelist the specific IP addresses that may need access in your phpMyAdmin.conf You can use more than one address. For instance:

   <IfModule mod_authz_core.c>
     # Apache 2.4
     <RequireAny>
      Require ip your.local.IP.address
      Require ip your.C#.app.IP.address
      Require ip 127.0.0.1
      Require ip ::1
     </RequireAny>
   </IfModule>
   <IfModule !mod_authz_core.c>
     # Apache 2.2
     Order Deny,Allow
     Deny from All
     Allow from your.local.IP.address
     Allow from your.C#.app.IP.address
     Allow from 127.0.0.1
     Allow from ::1
   </IfModule>

If you really need to allow all all IP addresses to access it, you can comment out the entire RequireAny section and change Deny from All to Allow from All

Remember to restart Apache after making any changes:

sudo service httpd restart

Solution that worked for me (Centos 7.3 Apache/2.4.6 (CentOS) PHP/5.4.16 phpMyAdmin-4.4.15.10-2.el7):

<Directory /usr/share/phpMyAdmin/>
   AddDefaultCharset UTF-8

   <IfModule mod_authz_core.c>
     # Apache 2.4
     <RequireAny>
       #ADD following line:
       Require all granted
       Require ip 127.0.0.1
       Require ip ::1
     </RequireAny>
   </IfModule>
   <IfModule !mod_authz_core.c>
     # Apache 2.2
     #CHANGE following 2 lines:
     Order Allow,Deny
     Allow from All
     Allow from 127.0.0.1
     Allow from ::1
   </IfModule>
</Directory>

thanks to chris

How do I know my your.C#.app.IP.address???

How to deny request:

::1 - - [01/May/2017:06:46:37 +0700] "OPTIONS * HTTP/1.0" 200 -

Thank