I'm back....
Still having trouble with RH9 and postfix 2.1.5. No mail coming or going.
There are no errors in the log files. postfix is running. Mail is listed in the Mail Queue but get a "message no longer in the queue" when I try to view. There is no mail in the user mailboxes.

I am not sure if this is a telnet problem or a postfix problem?
Following is some debug info to help you, help me.

when I type: # lsof -i tcp:25
I get:
COMMAND PID USER FD TYPE DEVICE SIZE NODE NAME
master 1737 root 11u IPv4 2532 TCP *:smtp (LISTEN)
smtpd 5461 root 6u IPv4 2532 TCP *:smtp (LISTEN)

when I type: # ps aux|grep postfix
I get:
root 1737 0.0 0.2 4720 564 ? S Apr19 0:00 /usr/libexec/postfix/master
postfix 1746 0.0 0.1 4796 408 ? S Apr19 0:00 nqmgr -l -n qmgr -t fifo -u -c
postfix 5968 0.0 0.6 4744 1456 ? S 20:02 0:00 pickup -l -t fifo -u -c
root 6205 0.0 0.2 3576 632 pts/0 S 20:10 0:00 grep postfix

When I type: # host relay-test.mail-abuse.org
I get:
relay-test.mail-abuse.org is an alias for cygnus.mail-abuse.org.
cygnus.mail-abuse.org has address 168.61.4.13

when I type: # telnet relay-test.mail-abuse.org
I get:
telnet: telnet: bad port

when I type: # telnet localhost 25
I get:
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
(then it just hangs there until I hit enter and exit)

when I type: # telnet my.ip.add.ress 25
I get:
Trying my.ip.add.ress...
Connected to my.ip.add.ress.
Escape character is '^]'.
(then it just hangs there until I hit enter and exit)

when I type: # telnet mail.mydomain.com 25
I get:
Trying my.ip.add.ress...
Connected to mail.mydomain.com.
Escape character is '^]'.
when I type: (no command prompt #)
MAIL FROM: webmaster@customshopping.com
I get:
Connection closed by foreign host.

when I type: # telnet mail.mydomain.com
I get:
telnet: telnet: bad port

my /etc/postfix/master.cf has:
# service type private unpriv chroot wakeup maxproc command + args
smtp inet n - n - - smtpd -v

Again any help would be wonderful...

PS.. This link gave me the most help! Thanks Overlord73 for leading me in the right direction to find it..

http://www.postfix-book.com/debugging.html

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