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So I have an Ubuntu Linux box machine for my website. (not ran locally at home, it is a public linux box). But for some strange reason I can only send Email from my home machine to this box in outlook. If I am on a different IP/Carrier I recieve a connection refused when I telnet.


$ telnet 25
telnet: Unable to connect to remote host: Connection refused

Inside House

$ telnet 25
Connected to
Escape character is '^]'.
220 ALLOCATETHIS-L101 ESMTP Postfix powered by Easy Hosting Control Panel (ehcp) on Ubuntu,

I don't see the error when looking mail.log either Below is my I am fairly new to postfix and would like to get this resolved.


# See /usr/share/postfix/ for a commented, more complete version

# Debian specific:  Specifying a file name will cause the first
# line of that file to be used as the name.  The Debian default
# is /etc/mailname.
#myorigin = /etc/mailname

smtpd_banner = $myhostname ESMTP $mail_name powered by Easy Hosting Control Panel (ehcp) on
biff = no

# appending .domain is the MUA's job.
append_dot_mydomain = no

# Uncomment the next line to generate "delayed mail" warnings
#delay_warning_time = 4h

readme_directory = /usr/share/doc/postfix

# TLS parameters
smtpd_tls_cert_file = /etc/postfix/smtpd.cert
smtpd_tls_key_file = /etc/postfix/smtpd.key
smtpd_use_tls = yes
smtpd_tls_session_cache_database = btree:${data_directory}/smtpd_scache
smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache

# See /usr/share/doc/postfix/TLS_README.gz in the postfix-doc package for
# information on enabling SSL in the smtp client.

myhostname = ALLOCATETHIS-L101
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailnamepostfix/cacert.pem
mydestination = localhost,
relayhost =
relay_domains = allocatethis.coma 3600s
mynetworks =,,,,
mailbox_size_limit = 0
recipient_delimiter = +
inet_interfaces = all
html_directory = /usr/share/doc/postfix/html
virtual_alias_domains =
virtual_alias_maps = proxy:mysql:/etc/postfix/, proxy:mysql:/etc/postfix/
transport_maps = proxy:mysql:/etc/postfix/
virtual_mailbox_domains = proxy:mysql:/etc/postfix/
virtual_mailbox_maps = proxy:mysql:/etc/postfix/
virtual_mailbox_base = /home/vmail
virtual_uid_maps = static:5000
virtual_gid_maps = static:5000
smtpd_sasl_auth_enable = yes
smtpd_sasl_security_options = noanonymous
broken_sasl_auth_clients = yes
smtpd_recipient_restrictions = permit_mynetworks,permit_sasl_authenticated,check_client_access hash:/var/lib/pop-before-smtp/hosts,reject_unauth_destinationsmtp_use_tls = yes
smtpd_tls_auth_only = no
smtpd_tls_CAfile = /etc/postfix/cacert.pem
smtpd_tls_loglevel = 1
smtpd_tls_received_header = yes
smtpd_tls_session_cache_timeout = 3600s
tls_random_source = dev:/dev/urandom
virtual_create_maildirsize = yes
virtual_mailbox_extended = yes
virtual_mailbox_limit_maps = proxy:mysql:/etc/postfix/
virtual_mailbox_limit_override = yes
virtual_maildir_limit_message = "The user you are trying to reach is over quota."
virtual_overquota_bounce = yes
debug_peer_list =
sender_canonical_maps =
debug_peer_level = 1
proxy_read_maps = $local_recipient_maps $mydestination $virtual_alias_maps $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains $relay_recipient_maps $cano$inet_protocols = all
smtpd_sasl_local_domain =
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You need to check your firewall settings. – Logic Wreck Sep 11 '12 at 16:49
I have, I have done this by disabling all firewall settings, and doing mobile check from phone, and tablets, gone to several friends houses in which we have disabled the firewall. – Darxval Sep 11 '12 at 16:58
up vote 1 down vote accepted

ISPs tend to block outbound connections to port 25/tcp in order to prevent botnet spam. Enable submission (port 587/tcp, must require authentication) in /etc/postfix/ and restart Postfix. Configure your mail client to submit mail via

share|improve this answer

The problem is related to your friends ISP.

telnet on port 25 works here.

# telnet 25
Connected to
Escape character is '^]'.
220 ALLOCATETHIS-L101 ESMTP Postfix powered by Easy Hosting Control Panel (ehcp) on Ubuntu,
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