diff --git a/install/sql/incremental/upd_dev_collection.sql b/install/sql/incremental/upd_dev_collection.sql
index 1544ea81b05ff51dd94724d0a9a3c6d616c2fa44..a12f9d482b0a58f71639d52a6dba96c3f0c17b4a 100644
--- a/install/sql/incremental/upd_dev_collection.sql
+++ b/install/sql/incremental/upd_dev_collection.sql
@@ -3,3 +3,6 @@ ALTER TABLE `web_domain` DROP COLUMN `fastcgi_php_version`;
 
 -- add php_fpm_socket_dir column to server_php
 ALTER TABLE `server_php` ADD `php_fpm_socket_dir` varchar(255) DEFAULT NULL AFTER `php_fpm_pool_dir`;
+
+-- fix #5939
+UPDATE `ftp_user` SET `expires` = NULL WHERE `expires` = '0000-00-00 00:00:00';
diff --git a/install/tpl/pureftpd_mysql.conf.master b/install/tpl/pureftpd_mysql.conf.master
index 484f1054c843555e273f9ac4d4141c43e2f40d13..fe3df27a3a938e4d679a16e96c85d73e8ecffd48 100644
--- a/install/tpl/pureftpd_mysql.conf.master
+++ b/install/tpl/pureftpd_mysql.conf.master
@@ -59,12 +59,12 @@ MYSQLCrypt      crypt
 
 # Query to execute in order to fetch the password
 
-MYSQLGetPW      SELECT password FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MYSQLGetPW      SELECT password FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
 # Query to execute in order to fetch the system user name or uid
 
-MYSQLGetUID     SELECT uid FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MYSQLGetUID     SELECT uid FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
 # Optional : default UID - if set this overrides MYSQLGetUID
@@ -74,7 +74,7 @@ MYSQLGetUID     SELECT uid FROM ftp_user WHERE active = 'y' AND server_id = '{se
 
 # Query to execute in order to fetch the system user group or gid
 
-MYSQLGetGID     SELECT gid FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MYSQLGetGID     SELECT gid FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
 # Optional : default GID - if set this overrides MYSQLGetGID
@@ -84,34 +84,34 @@ MYSQLGetGID     SELECT gid FROM ftp_user WHERE active = 'y' AND server_id = '{se
 
 # Query to execute in order to fetch the home directory
 
-MYSQLGetDir     SELECT dir FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MYSQLGetDir     SELECT dir FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
-# Optional : query to get the maximal number of files 
+# Optional : query to get the maximal number of files
 # Pure-FTPd must have been compiled with virtual quotas support.
 
-MySQLGetQTAFS  SELECT quota_files FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND quota_files != '-1' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MySQLGetQTAFS  SELECT quota_files FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND quota_files != '-1' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
 # Optional : query to get the maximal disk usage (virtual quotas)
 # The number should be in Megabytes.
 # Pure-FTPd must have been compiled with virtual quotas support.
 
-MySQLGetQTASZ  SELECT quota_size FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND quota_size != '-1' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MySQLGetQTASZ  SELECT quota_size FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND quota_size != '-1' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
 # Optional : ratios. The server has to be compiled with ratio support.
 
-MySQLGetRatioUL SELECT ul_ratio FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND ul_ratio != '-1' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
-MySQLGetRatioDL SELECT dl_ratio FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND dl_ratio != '-1' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MySQLGetRatioUL SELECT ul_ratio FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND ul_ratio != '-1' AND username="\L" AND (expires IS NULL OR expires > NOW())
+MySQLGetRatioDL SELECT dl_ratio FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND dl_ratio != '-1' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 
 # Optional : bandwidth throttling.
 # The server has to be compiled with throttling support.
 # Values are in KB/s .
 
-MySQLGetBandwidthUL SELECT ul_bandwidth FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND ul_bandwidth != '-1' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
-MySQLGetBandwidthDL SELECT dl_bandwidth FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND dl_bandwidth != '-1' AND username="\L" AND (expires IS NULL OR expires="0000-00-00 00:00:00" OR expires > NOW())
+MySQLGetBandwidthUL SELECT ul_bandwidth FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND ul_bandwidth != '-1' AND username="\L" AND (expires IS NULL OR expires > NOW())
+MySQLGetBandwidthDL SELECT dl_bandwidth FROM ftp_user WHERE active = 'y' AND server_id = '{server_id}' AND dl_bandwidth != '-1' AND username="\L" AND (expires IS NULL OR expires > NOW())
 
 # Enable ~ expansion. NEVER ENABLE THIS BLINDLY UNLESS :
 # 1) You know what you are doing.