Server dovecot: auth: Warning: sql: Ignoring changed iterate_quer

Hello, 

I am having an issue with Dovecot. I am using Roundcube to access my mailboxes, which I have set up using ViMbAdmin. 

However when I go to the Roundcube, I get login Failed. 

So looking in the mail.log I can see the following: 

Aug 15 13:20:09 Server dovecot: auth: Warning: sql: Ignoring changed iterate_query in /etc/dovecot/dovecot-sql.conf.ext, because userdb sql not used. (If this is intentional, set userdb_warning_disable=yes)

Aug 15 13:20:11 Server dovecot: imap-login: Disconnected (auth failed, 1 attempts in 2 secs): user=joe@anoblequest.co.uk, method=PLAIN, rip=62.49.15.89, lip=192.168.0.90, TLS, session=

I am most greatful for the support

Joe :)