Drupal File permissions on Plesk 11.5 with PHP-FPM and NGINX
in PHP_FPM PHP runs with the FTP user permissions.
create tmp directory at default/files/tmp
chmod -R 757 default/files
chmod -R 757 default/private_files
chmod 755 default
After that change the tmp file location in http:///admin/config/media/file-system
to default/files/tmp (the one created above)
and Drupal seems happy.
No errors reported.