To enable PHP support, Please follow the following settings:-
1) Login to Plesk control panel.
2) Click on "Subscription".
3) Click on "Manage Hosting" in front of the domain whose files permission you want to change.
4) Click on "Websites and Domains" Scroll Down then go to "Domain name".
5) Click on the "domain name" under whom you want to enable PHP support.
6) Click on Check box in front of "Disable / Enable PHP Scripting ( PHP / CGI )
7) Click on "OK" once you have enabled the PHP support.
