I have installed proftpd on a new x86_64 server: [root@ftp ~]# uname -a Linux ftp.csdsinc.com 2.6.9-22.0.1.ELsmp #1 SMP Thu Oct 27 14:49:37 CDT 2005 x86_64 x86_64 x86_64 GNU/Linux CentOS release 4.2 (Final) Proftpd Ver: [root@ftp ~]# rpm -q proftpd proftpd-1.2.10-8.2.el4.rf Selinux is disabled Modified debug file excerpt: xxx.xxxxx.com - ProFTPD 1.2.10 (stable) (built Fri Feb 18 05:56:53 CET 2005) standalone mode STARTUP xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - FTP session requested from unknown class xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - connected - local : xx.xx.xx.xx:21 xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - connected - remote : xx.xx.xx.xx:2208 xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - FTP session opened. xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'USER wells' to mod_tls xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'USER wells' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'USER wells' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'USER wells' to mod_auth xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching CMD command 'USER wells' to mod_auth xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching LOG_CMD command 'USER wells' to mod_log xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'PASS (hidden)' to mod_tls xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'PASS (hidden)' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'PASS (hidden)' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'PASS (hidden)' to mod_auth xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching CMD command 'PASS (hidden)' to mod_auth xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - PAM(wells): Module is unknown. xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - USER wells (Login failed): Incorrect password. xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching LOG_CMD_ERR command 'PASS (hidden)' to mod_log xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching LOG_CMD_ERR command 'PASS (hidden)' to mod_auth xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'QUIT' to mod_tls xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'QUIT' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'QUIT' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching PRE_CMD command 'QUIT' to mod_log xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - dispatching CMD command 'QUIT' to mod_core xxx.xxxxx.com (xx.xx.xx.xx[xx.xx.xx.xx]) - FTP session closed. This is a copy of a working server i386 running: [em@helpdesk em]$ uname -a Linux helpdesk.csdsinc.com 2.4.21-37.EL #1 Wed Sep 28 14:14:23 EDT 2005 i686 i686 i386 GNU/Linux CentOS 3.6, proftpd-1.2.10-8.1.el3.dag The 3.6 box works and the 4.2 box will not authenticate any user. I'm concernesd with the "PAM(wells): Module is unknown." Any ideas?