disable quota for all users

[Support Antenna]

Dear all,

On a new server (postfix dovecot postfixadmin Centos)
I did define quota=0 in postfixadmin

However suddenly a user with more than 9Gb of mail got his mailbox new/cur 
empty and maillog shows:

Sep  3 15:43:56 mail16 dovecot: lda(brouwerb at scholarium.nl): Error: sieve: 
msgid=<alpine.LRH.2.20.1509031543050.16381 at streaming2.antenna.nl>: failed 
to store into mailbox 'INBOX': Quota exceeded (mailbox for user is full)
Sep  3 15:43:56 mail16 dovecot: lda(brouwerb at scholarium.nl): Error: sieve: 
script /home/sieve/globalfilter.sieve failed with unsuccessful implicit 
keep
Sep  3 15:43:56 mail16 dovecot: lda(brouwerb at scholarium.nl): 
msgid=<alpine.LRH.2.20.1509031543050.16381 at streaming2.antenna.nl>: 
rejected: Quota exceeded (mailbox for user is full)


Apparently somewhere a quota is defined, probably in dovecot

cd /etc/dovecot
grep -R quota * |grep -v "#"
conf.d/auth-vpopmail.conf.ext:  args = 
quota_template=quota_rule=*:backend=%q
dovecot.conf:  mail_plugins = quota sieve
dovecot.conf:  mail_plugins = quota imap_quota trash
dovecot.conf:  mail_plugins = quota
dovecot.conf:  quotadict = mysql:/etc/dovecot/dovecot-dict-quota.conf
dovecot.conf:  quota = dict:user::proxy::quotadict
dovecot-dict-quota.conf:  pattern = priv/quota/storage
dovecot-dict-quota.conf:  table = quota2
dovecot-dict-quota.conf:  pattern = priv/quota/messages
dovecot-dict-quota.conf:  table = quota2
dovecot-mysql.conf:user_query = SELECT concat('/home/vmail/', maildir) as 
home, concat('maildir:/home/vmail/', maildir) as mail, 101 AS uid, 12 AS 
gid, CONCAT('*:messages=10000:bytes=', quota) as quota_rule FROM mailbox 
WHERE username = '%u' AND active = '1'

Output of dovecot -n :

# 2.0.9: /etc/dovecot/dovecot.conf
# OS: Linux 2.6.32-573.3.1.el6.x86_64 x86_64 CentOS release 6.7 (Final) 
ext4
auth_mechanisms = plain login
dict {
   quotadict = mysql:/etc/dovecot/dovecot-dict-quota.conf
}
first_valid_gid = 12
first_valid_uid = 101
lda_mailbox_autocreate = yes
lda_mailbox_autosubscribe = yes
lmtp_save_to_detail_mailbox = yes
mail_location = maildir:/home/vmail/%d/%n
managesieve_notify_capability = mailto
managesieve_sieve_capability = fileinto reject envelope encoded-character 
vacation subaddress comparator-i;ascii-numeric relational regex imap4flags 
copy include variables body enotify environment mailbox date
passdb {
   args = /etc/dovecot/dovecot-mysql.conf
   driver = sql
}
plugin {
   acl = vfile:/etc/dovecot/acls
   quota = dict:user::proxy::quotadict
   sieve = ~/dovecot.sieve
   sieve_dir = ~/sieve
   sieve_global_dir = /home/sieve/
   sieve_global_path = /home/sieve/globalfilter.sieve
   sieve_max_script_size = 1M
   trash = /etc/dovecot/trash.conf
}
protocols = imap pop3 lmtp sieve
service auth {
   unix_listener /var/spool/postfix/private/auth {
     group = postfix
     mode = 0666
     user = postfix
   }
   unix_listener auth-userdb {
     group = mail
     mode = 0666
     user = vmail
   }
}
service dict {
   unix_listener dict {
     group = mail
     mode = 0666
     user = vmail
   }
}
service imap-login {
   inet_listener imap {
     port = 143
   }
   inet_listener imaps {
     port = 993
     ssl = yes
   }
}
service imap {
   vsz_limit = 256 M
}
service managesieve-login {
   inet_listener sieve {
     port = 4190
   }
   process_min_avail = 0
   service_count = 1
   vsz_limit = 64 M
}
service pop3-login {
   inet_listener pop3 {
     port = 110
   }
   inet_listener pop3s {
     port = 995
     ssl = yes
   }
}
ssl_ca = </etc/pki/tls/certs/PositiveSSL_Bundle.crt
ssl_cert = </etc/pki/tls/certs/webmail2.antenna.nl.crt
ssl_key = </etc/pki/tls/certs/webmail2.antenna.nl.key
ssl_verify_client_cert = yes
userdb {
   driver = prefetch
}
userdb {
   args = /etc/dovecot/dovecot-mysql.conf
   driver = sql
}
protocol lda {
   mail_plugins = quota sieve
   postmaster_address = postmaster at antenna.nl
}
protocol imap {
   imap_client_workarounds = delay-newmail
   mail_plugins = quota imap_quota trash
}
protocol lmtp {
   mail_plugins = sieve
}
protocol pop3 {
   mail_plugins = quota
   pop3_client_workarounds = outlook-no-nuls oe-ns-eoh
}
protocol sieve {
   managesieve_implementation_string = Dovecot Pigeonhole
   managesieve_max_compile_errors = 5
   managesieve_max_line_length = 65536
}


What should be changed where to disable quota (as to messages and space)?


Thanks a lot,

warm regards,

Tsjêbbe