0
votes
1answer
25 views

Should I block the other SMTP ports as well to block outgoing mail?

I have blocked outgoing port 25 to prevent spam being sent from my servers. However, I'm not very familiar with SMTP and I have heard that ports such as 465 and 587 can also be used to send mail, but ...
-4
votes
0answers
18 views

Own company SMTP-server but feasible due to SPAM [closed]

Our company is growing. We want to set up an own e-mail-server. For this reason we are renting a root-server. This root-server has a static ip. This means we have to install a pop3/imap-server on our ...
-1
votes
0answers
26 views

SMTP Postfix server probably used as a spam relay : how to protect? [duplicate]

I'm using my own mail server to send and receive emails : a Debian 6.0.7 running Postfix 2.7.1 and Courier. Today, I'm suspecting that this server is used as a SMTP relay for spammers... The clues are ...
0
votes
0answers
37 views

SPF record validation is pass but email is rejected by server [duplicate]

I have SMTP on a windows 2008 server with IIS6. The SPF recored is passed when I send emails to hotmail or gmail but it gets rejected on other servers claiming that there is problems with the SPF. ...
2
votes
1answer
55 views

How easy is it to sniff the SMTP port of webserver to capture mails

I've got a very basic question that I don't know the answer for. Our company owns a webserver that runs multiple websites and works as a mail server for these websites as well (e.g. to send contact ...
0
votes
1answer
52 views

hMail delivery queue full with unsuccesfull spam

Since a day or two the mail delivery queue of the hMailServer is exploding because someone is trying to send spam via this server. Though the e-mails aren't successfully sent it fills up the mail ...
0
votes
1answer
65 views

What do I need to be able to send mass SMTP email efficiently? [closed]

I am creating a web application that allows users to send broadcast emails to a list of subscribers. Essentially, it's a mass emailer and autoresponder, like AWeber or Constant Contact or MailChimp. ...
0
votes
1answer
111 views

Postfix: mail going to spam [duplicate]

All emails I send from my new server go to spam in Gmail (and sometimes yahoo). I've never before sent out mass email or spam. What I've already done: Configured reverse DNS Enabled DKIM Verified ...
0
votes
1answer
175 views

SPF + ISP Smarthost, always untrusted?

One of the ways mail-servers protect themselves from spam is by SPF-records, a DNS look-up saying what ip-adresses are allowed to send mail from a given domain name. Another way the mail-servers use ...
1
vote
0answers
52 views

Configure postfix to limit total number of connections from any and all SMTP clients in a given time period?

I am trying to figure how to configure Postfix to operate within the requirements given by Spamhaus for free usage of their DNSBLs (http://www.spamhaus.org/organization/dnsblusage/). They specify that ...
0
votes
1answer
56 views

Spamming from Exchange 2003

I am apparently spamming the world (about 1000 a day) but cannot figure out how. Mxtoolbox does not list me as an open relay and I have disabled all relays that I can find. I have run every virus ...
-1
votes
1answer
291 views

Spam Filters - Why does the same message fail via one smtp server but not the other?

I have a PHPMailer script sending email. If sent via postfix localhost it is marked as spam with these headers. Delivered-To: xxxx Received: by 10.58.210.166 with SMTP id mv6csp82473vec; Sun, ...
0
votes
0answers
37 views

Can someone explain SMTP Callbacks when BATV is enabled, and when to issue the verification?

This Wikipedia article describes how SMTP verification of the MFROM may have issues if BATV is enabled. Servers that reject all bounce mails (contrary to the RFCs). To work around this problem, ...
1
vote
1answer
91 views

Reverse DNS lookup not resolving correctly

I've been searching and searching for the answer and I can't find it. My problem is that all of my emails sent from my server are either going to spam folders or not being delivered. I am trying to ...
2
votes
1answer
215 views

Exchange Server 2010 Relaying Spam

Recently I began receiving AOL spam feedback reports from our exchange server. As I investigated I found that hundreds of spam messages were being relayed through our exchange server. Although I am ...
1
vote
1answer
52 views

Advertise NO-SOLICITING (RFC3865)

Does it bring anything to specify the Solicitation class keywords in Advertise NO-SOLICITING as per RFC-3865? For instance: dom.spammer:ADLT,dom.listing:ADV
0
votes
1answer
226 views

How to find which local process is sending spam on a Windows Server 2008 server

I am managing a Win Server 2008 system with a number of hosted web sites. Recently I found that something was sending spam through our SMTP server. The logs indicate that the connections were being ...
2
votes
1answer
4k views

What is preferable, “no-reply@” or “noreply@”? [closed]

Having a service that sends out notifications to users, I'm currently thinking about changing the sender email address from "info@" to something more meaningful. Since a reply never makes sense, I'm ...
0
votes
1answer
225 views

GoogleApps mail going in spam folder

Like I mentioned in title I have a problem with my mail, Google treated them as spam. On my VPS I have CentOS 5 Kloxo Host-InA-Box. So I set all 5 mx records for GoogleApps: conmendo.com MX 10 ...
0
votes
1answer
424 views

Extreme headache from ASSP Extreme Ban

I've got a local user on my server that as of today cannot send email from any of their devices. Only Webmail (which doesn't touch any of their devices) works. Here are the various email failures I'm ...
1
vote
1answer
443 views

Log with iptalbes which user is delivering email to port 25

Because we got blacklisted on CBL I set up the following firewall rules with iptables: #!/bin/bash iptables -A OUTPUT -d 127.0.0.1 -p tcp -m tcp --dport 25 -j ACCEPT iptables -A OUTPUT -p tcp -m tcp ...
1
vote
2answers
490 views

Spam mail through SMTP and user spoofing [closed]

I have noticed that it's possible to telnet into a mailserver that I own and send spoofed messages to other clients. This only works for the domain that the mail server is regarding; I cannot do it ...
31
votes
4answers
3k views

Is greylisting still an efficient method for preventing spam?

I've used greylisting on my servers for many years, but I don't know how effective it is nowadays. Is it still good for fighting spam in 2012? Or is the typical spammer MTA capable of resending ...
0
votes
2answers
144 views

How often do MXLogic lists get updated?

Some domain refused to accept email from my domain due to MXLogic filtering. I've sent an email to falsepositives@mxlogic.com and they responded promptly that they changed their records. Question: ...
4
votes
3answers
356 views

With regard to anti-spam practices, what exactly does a typical reverse DNS check look for?

My understanding is that a typical reverse DNS lookup will compare the SMTP hostname (provided in the EHLO/HELO command) of an incoming connection and verify that it matches the PTR record for the ...
1
vote
1answer
95 views

Anti-spam: allow only authorized SMTP servers

Spam is a huge problem these days, especially spam sent with your e-mail address as the sender. I think I have a simple solution but I'd like to hear from you what is wrong with it or why it is ...
2
votes
1answer
63 views

What is the benefit of using DKIM to sign Content Type?

DKIM has the ability to sign headers on a per-header basis. I looked at Google's headers, and they DKIM sign ContentType. What is the security benefit of signing ContentType?
0
votes
1answer
75 views

What I can do to achieve this kind of smtp proxy

I'm providing VPS services and I don't want my IP addresses spoiled by spammers. What I want to achieve here is to route all the outbound traffic to some sort of smtp proxy server which will just let ...
1
vote
2answers
343 views

Postfix - Block email from non-existent local addresses

My question is very similar to this one, but for postfix. We keep getting emails from addresses like "accounting@example.com" delivered to our actual "@example.com" addresses. From my google ...
0
votes
2answers
294 views

Postfix and myhostname/mydomain

I currently have Postfix running on a box that also hosts a number of websites. Although the website domains' DNS all have an A record pointing to this server, the server has no hostname of its own. ...
-3
votes
1answer
336 views

Email header analysis

I have an email header which is showing the following information, which i believe is faked. The mail purports to be from a gmail account but I'm not sure if this is the case. Ordinarily you read the ...
0
votes
3answers
3k views

smtp 554 rejected - poor reputation

My SMTP (e-mail server) do not send e-mails for 99% of the tries. Log SMTP server hMailServer: "SMTPD" 1092 17 "2012-02-09 12:55:20.328" "173.44.33.116" "RECEIVED: DATA" "SMTPD" 1092 17 ...
0
votes
1answer
88 views

SMTP filtering proxy

I provide SSH shells to a lot of people and block port 25, 465 and so on by default via iptables to avoid that some people send spam messages. Is there some kind of SMTP filtering proxy or -gateway ...
2
votes
1answer
206 views

Configure exim4 (or other MTA) to prevent sending duplicate emails

How can I configure exim4 (or another MTA) to avoid sending duplicate emails? For my purposes a duplicate email can be defined as: same recipient and subject (or same recipient, subject and body) I ...
0
votes
2answers
291 views

Media Temple, SPF, and Changing IP Addresses

OK...so I have a hosting account with Media Temple and recently had problems with mail servers marking my sent emails as SPAM. I looked into the issue and read it's a good idea to implement SPF which ...
2
votes
1answer
211 views

How do I configure my domain and web application so the emails send from the latter are not blocked as spam?

I have a WordPress site that needs to send notifications to an email address. I would like the from field from this emails to be an address on my client's domain. I dont know much about email ...
1
vote
2answers
764 views

What should be the spf record for my domain?

I have my own registered domain. I have a dedicated IP for my domain. I use a shared hosting service for my website. I want to send mail with php's function mail();. I have created one email ...
0
votes
3answers
174 views

Sending email from a 3rd-party-hosted server

We contracted with a 3rd party vendor to build and host a web application for us. The web app will need to send email notifications out to users when they request it. The application is not hosted ...
-3
votes
2answers
266 views

delete spam with mailenable [closed]

I am using mailenable on my VPS server. How can I set up mailenable to checking incoming emails to my server if they are spam or not and if so, delete them?
2
votes
1answer
180 views

Issue of tracking an email that was “lost in cyberspace”

The issue here is one of an email that has been "lost in cyberspace." The receiver is claiming never to have received it. However, I recieved an automated out-of-office reply as a response to my ...
4
votes
2answers
4k views

How to read the “MS ForeFront” antispam report in email header?

I'm trying to diagnose why emails I'm sending out from my server's IIS SMTP Pickup Folder are getting bounced back occasionally. One tech from a receiving company who couldn't receive the emails ...
2
votes
1answer
129 views

Sending email from specific vhost, bad for spam?

Essentially, I have a server that contains many vhosts. One vhost in particular is required to send mail from the address invitations@vhost.com, however the reverse DNS for that server resolves to ...
0
votes
2answers
2k views

Windows 2003 Server IIS SMTP Sending SPAM

we have a Windows 2003 Server using IIS6 for SMTP and Websites. A couple of weeks ago the server started to send out SPAM emails. I'm trying to figure out how to identify where the SPAM is coming ...
1
vote
2answers
2k views

Postfix - am I sending spam?

today I received like 30 messages within 5 minutes telling me that some mail I send could not be delivered, mostly to *.ru email addresses which I did not send any mail to. I have my own webserver ...
0
votes
2answers
664 views

Strange email coming from/to my computer

I'm running smtp4dev on my machine to trap anything going in/out of my computer on port 25 for testing purposes. Every so often this email gets trapped and I have no idea what it's from. I have ...
1
vote
1answer
62 views

Postfix/Rejecting mails

How do I make Postfix to reject all mails if the client is not authenticated and to sender is @mydomain? Is the an easy way to do this? Max
0
votes
1answer
642 views

postfix smtp_get: EOF

I'm using postfix (incomming port 25) + SpamPD (127.0.0.1:10025 relayhost:127.0.0.1:10026) for filtering incoming email, which are coming from internet for my remote MTA. MTA which holds virtual ...
2
votes
6answers
164 views

Does disallowing sending emails via a SMTP server that doesn´t have the same address help preventing spam or is it dangerous?

I am working in a small programming company and administrated the mail-servers for quite a while. Now we moved our web site and the MTA to a company that we considered to be more professional. But I ...
1
vote
1answer
491 views

Multipart messages from postfix go to spam in gmail/hotmail

I'm new here and I'm sure this question has been thrown around a lot but I just couldn't find a solution. I have a networking website I've setup and we need to send notification mails to our members ...
0
votes
2answers
161 views

How do i know email sending limit not to be declared as spammer?

I need to implement in our CRM the mass email sending from our customers to their contacts. I am sorry this might be trivial question, but i maybe dont know what keywords to use to google it, how do i ...