Webftp (Net2Ftp) Trouble...

After installation everything working fine except for Webftp (Net2Ftp) that comes with an error page as follows:

An error has occurred:

Unable to execute the SQL query.

The error occurred in file /var/www/vhosts/ehcp/net2ftp/includes/authorizations.inc.php on line 728.
• function logAccess (/var/www/vhosts/ehcp/net2ftp/main.inc.php on line 213)
• function net2ftp (/var/www/vhosts/ehcp/net2ftp/index.php on line 38)
o argument 0: sendHttpHeaders

Someone have any idea what it can be or how to fix it?

I followed that and now evething is fine. Thank you.