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cannot telnet to port 25 from another machine

I have done the following but can sendmail from local but cannot send email&telnet port 25 from anther machine:

- disabled firewall
[root@officemail xinetd.d]# iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination
[root@officemail xinetd.d]#

add in /etc/mail/access:
10.128                          RELAY
10.129                          RELAY

makemap hash /etc/mail/access < /etc/mail/access

vi /etc/mail/sendmail.mc
changed to DAEMON_OPTIONS(`Port=smtp,Addr=, Name=MTA')dnl

m4 /etc/mail/sendmail.mc > /etc/mail/sendmail.cf
service sendmail stop
killall -HUP sendmail
service sendmail start

[root@officemail ~]# telnet localhost 25
Connected to localhost.localdomain (
Escape character is '^]'.
220 officemail ESMTP Sendmail 8.13.1/8.13.1; Wed, 29 May 2013 16:59:55 +0800
221 2.0.0 officemail closing connection
Connection closed by foreign host.
[root@officemail ~]# netstat -vat
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address               Foreign Address             State
tcp        0      0 *:936                       *:*                         LISTEN
tcp        0      0 *:sunrpc                    *:*                         LISTEN
tcp        0      0 *:auth                      *:*                         LISTEN
tcp        0      0 *:smtp                      *:*                         LISTEN
tcp        0      0 *:ssh                       *:*                         LISTEN
tcp        0     52 ::ffff:   ::ffff:   ESTABLISHED
tcp        0      0 ::ffff:   ::ffff:   ESTABLISHED
[root@officemail ~]#


but from another pc in the same subnet:

G:\>telnet 25
Connecting To not open connection to the host, on port 25
: Connect failed


how come?

1 Solution
Gerwin Jansen, EE MVETopic Advisor Commented:
Any firewall / antivirus software installed on that PC?

Have a look in the antivirus log file, it could be blocking port 25.
HobolyAuthor Commented:
Great! haha
you're right
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