限制从外部访问phpMyAdmin，但不能通过localhost

Question

I currently have phpMyAdmin setup on an IIS Server, it is available externally to all users, I wish to have this available only through localhost when connected to the server. The following code is used in the web.config file and placed in the phpMyAdmin directory:

<configuration>
 <security>
  <ipSecurity allowUnlisted="false">               
    <clear/>
    <add ipAddress="127.0.0.1" allowed="true"/>                    
  </ipSecurity>
 </security>

However this displays an internal server error, I'm pretty sure the script is missing something or needs amending. Any help would be great.

Many thanks.