When creating a domain in Plesk, PHP safe_mode is enabled by default. To change the default behavor do the following as the admin:
- On the home screen in Plesk go to Event Manager
- Click on Add New Event Handler
- Fill in the form with the following values:
Event: Physical Hosting Created
Priority: default is fine
User: root
Command: /usr/local/psa/bin/domain -u <new_domain_name> -php_safe_mode false