By default Plesk applies open_basedir restriction for all the domains on the server. You can remove the open_basedir restriction lines from the httpd.include file located at /home/httpd/vhosts/example.com/conf/ directory but Plesk will overwrite the file again once it rebuild the include files.

To permanently remove the open_basedir restrictions for a domain, create a vhost.conf file

vi /home/httpd/vhosts/example.com/conf/vhost.conf

and place the following lines:

<Directory /home/httpd/vhosts/example.com/httpdocs/>
php_admin_value open_basedir none
</Directory>

Once done, rebuild the include file with the command:

/usr/local/psa/admin/bin/websrvmng -a

and restart the Apache service:

service httpd restart

To verify the new settings, place a phpinfo.php file under the account, browse the file and check the “Local Value” column.