unable to correctly install PHP

[nthom58]

I have followed the instructions in setting up a PHP development environment (xp), Apache and MYSQL is running but when I click"Test URL" I get the following message "Dreamweaver cannot used the prefix you entered to display live data" There are my settings:
Site name MyWebApp2
Local root folder c:\xampp\htdocs
http address http://localhost/MyWebbApp2/">http://localhost/MyWebbApp2/
server model PHP/SQL
Access Local/Network
Testing server folder c:\xampp\htdocs
URL prefix http://localhost/MyWebbApp2/
I get a similar message when I try to view a web page with PHP in.
Can anyone be so kind and point out what I am doing wrong as I have spent hours trying to get this to work.
Thanks Norm

[nthom58]

I might add that these are the settings in Dreamweaver to set up a site