I have used Falkos HowTo on the virtual users, domains etc on Postfix and Courier without any problems for many years (since Ubuntu 10.04), but I have lately upgraded my server to ubuntu 16.04 with a fresh install, and with MariaDB in place of MySQL. Just about everything works, except I cant get the pesky thing to authenticate. So I've set Courier-imap logging to maximum and this i what I get: Code: Aug 18 20:38:37 hostname imapd: Connection, ip=[IP.ADDRESS] Aug 18 20:38:37 hostname authdaemond: received auth request, service=imap, authtype=login Aug 18 20:38:37 hostname authdaemond: authmysql: trying this module Aug 18 20:38:37 hostname authdaemond: authmysqllib: connected. Versions: header 50711, client 50713, server 50505 Aug 18 20:38:37 hostname authdaemond: SQL query: SELECT email, password, "", 5000, 5000, "/home/vmail", CONCAT(SUBSTRING_INDEX(email,'@',-1),'/',SUBSTRING_INDEX(em$, quota, "", "" FROM users WHERE email = [email protected][email protected][email protected][email protected] It's very obvious there is something wrong with the query (no closing parenthesis in second ´SUBSTRING_INDEX'), but I'm at a loss as to how and where to remedy this so the correct query gets submitted to the authentication daemon. With testsaslauthd I get a simple "connect() : Permission denied" Is there anyone here who can point me in the right direction?