Php ini not updating
You can make changes on a per domain basis via a .htaccess file. Plesk 11.0 and later features a domain-specific file. You can select common options from the drop-down menus, or create your own by using the "Custom Variable" option.
This domain-level version of overrides the global settings. You can edit the domain-level file through the Plesk Control Panel. For directives that are not listed, raw text can be input in the box at the bottom of this screen.
See: Increasing memory allocated to PHP The file was updated by technical support (memory_limit 128 M 128 M), but the error is still appearing in Wordpress. The setting only works in the exact folder it lives in by default.
If you want it to work for all other folders and files, you will need to be sure you make it recursive within your .htaccess file.
Installing, configuring, and troubleshooting third-party applications is unsupported by (mt) Media Temple.