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Ive been trying to configure my postfix with virtual users, but I have a problem, with my port 25 on the client nothing works, so, if i change /etc/postfix/ and i change

smtp inet n - - - - smtpd


26 inet n - - - - smpt , it works, read the mails I sent before set that port and I can send mails, but later, if I send more mails, it just dont get them... but I still can send.

I tried with the port 587 but I still have that problem. I really dont know whats wrong.

I created a mx register that points to (instead or

When I test the configuration on my client (Outlook) it doesnt show any errors, like if would be reading all, but I guess when I change the port the connection is being refused

Here is what i set on my postfix/

myhostname =
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
myorigin = /etc/mailname
mydestination =
relayhost =
mynetworks = [::ffff:]/104 [::1]/128
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/, 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
broken_sasl_auth_clients = yes
smtpd_sasl_authenticated_header = yes
smtpd_recipient_restrictions = permit_mynetworks, permit_sasl_authenticated, reject_unauth_destination
transport_maps = proxy:mysql:/etc/postfix/
virtual_create_maildirsize = yes
virtual_maildir_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
proxy_read_maps = $local_recipient_maps $mydestination $virtual_alias_maps $virtual_alias_domains $virtual_mailbox_maps $virtual_mailbox_domains $relay_recipient_maps $relay_domains $canonical_maps $sender_canonical_maps $recipient_canon$
content_filter = amavis:[]:10024
receive_override_options = no_address_mappings

I checked my ports 587 and 110 and they both return they are opened.

Any idea about this issue?



I moved to the port 25 again, it receives very good.. but cant send, im sending on webmail, makes me think its a policy of isp (due port 25) still, when I change the port to 587 sends but doesnt receive (which has no sense, port 110 to download should be working).

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closed as off-topic by Dennis Kaarsemaker, Tom O'Connor Aug 26 '13 at 23:56

This question appears to be off-topic. The users who voted to close gave this specific reason:

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Why do you need non standard port at all? And how in such case remote smtp server will contact with your postfix? – ALex_hha Aug 26 '13 at 17:28
thank u, i cant use port 25 because at some mobile internet (due the isp) here, are locked, and cant use that port – jpganz18 Aug 26 '13 at 18:02
You should be authenticating when using port 587 are you? What does your server's maillog say? Also 587 tends to have -o smtpd_tls_security_level=encrypt set in, which means your server needs certificates (which is should have anyway, lest you send your password in the clear, even wose that it would also be over wireless where anyone, no just the ISPs can sniff). – 84104 Aug 26 '13 at 19:04
im going to check it, thanks! – jpganz18 Aug 26 '13 at 19:22
up vote 1 down vote accepted
  1. Changing the port that your SMTP server listens on will have zero effect on outbound mail.
  2. If your server isn't listening on port 25 then you're not going to get any mail because there's no way for the sending servers out on the internet to know that you're running on a non-standard port.
  3. If your ISP is blocking port 25 [inbound and/or outbound] then you need to resolve that with your ISP. If you're on a non-business-class plan I wouldn't expect them to remove the block on port 25.
  4. Unless you plan for this to be a long and very painful learning experience I would suggest having your mail hosted by another company, because you're clearly new to this.
share|improve this answer
there is no way they recognize im not over the port 25? why at some web hosting services tell u to use port 26? and u can get and send mails with no problem? – jpganz18 Aug 26 '13 at 21:43
@jpganz18 That works between client and server because there are two people [editor's note: 'sacks of meat' is not a generally-acceptable substitution for the term 'people'] communicating that fact outside the context of the SMTP connection. For server-to-server email delivery the sending server will attempt to open port 25 on the destination server, fail, retry port 25 repeatedly [for up to 2 days, maybe more], and eventually bounce the message back to the sender. – Sammitch Aug 26 '13 at 22:24

I'm sure to be punished harshly for an answer like this but it's true so I must give it. Ordinary users (and most IT admins) should NEVER create their own mail servers. You weren't properly trained for this, your ISP doesn't want it, it's probably against your service contract to do this, to achieve and maintain security on the system properly will take more time than you're going to give it, messing up the security will hurt others, and the punishment for doing it wrong can be harsh (getting removed from most blacklists once placed on them is not usually very easy).

Why bother? When there are thousands of competitively priced email services out there? In the end your company is going to waste more money paying you to figure out that you aren't qualified than 5 years of a paid service would cost. Ohh ya, Google is free for most businesses too (meaning that you've already spent more than you should've by posting this question alone).

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+1 for the Google. – Sammitch Aug 26 '13 at 20:50

You don't understand clearly. If the ISP is blocking 25 port no one from the outside world is going to be able to send mail to you. If you want to receive mail from anyone you need your ISP to open 25 port.

share|improve this answer
no, thats why i want to send through another port, not the 25 – jpganz18 Aug 26 '13 at 21:42
thanks, i let it in the port 25... thanks! – jpganz18 Aug 27 '13 at 15:25

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