Various techniques are used to prevent email spam (unsolicited bulk email). No technique is a complete solution to the spam problem, and each has trade-offs between incorrectly rejecting legitimate email (false positives) vs. not rejecting all spam (false negatives) - and the associated costs in time and effort. Anti-spam techniques can be broken into four broad categories: those that require actions by individuals, those that can be automated by email administrators, those that can be automated by email senders and those employed by researchers and law enforcement officials.

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We have a problem with an SMTP send farm. All public IP of the farm are blacklisted by Spamcop and we can't request a new delisting.

We are using an antispam filter for INcoming & OUTgoing mails. No mail can be send is a domain doesn't exist on our system. I download the list of sender contacted today & I tried to identify a problem on the list. But I found nothing suspect...

I think there is one (or many) mail adresses used by spamcop as "trap" to identify spam sender.

Have some advice to help me to solve this problem ?

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Scrollout F1 is setup as a SPAM inbound gateway to an Exchange server.  We have some senders whos emails won't deliver to the Exchange server.  Thus far the emails have not kicked back.  The remote Exchange server is stating the message delivery has been delayed.  I am assuming Scrollout is terminating the connection from the remote mail server.  I did notice that the remote domain doesn't have an SPF record.  Would that be enough to cause this issue?  What can I do i Scrollout to mitigate the issue so we can receive their emails?  I don't see anything in the logs of the web interface that report any activity for the remote server domain.  Are there other logs on the Scrollout file system that I should be looking at?

Any help would be appreciated
You have a secure Document from . Open message below

 click here.

Note; Your email and your password is required for authentication.

Can you please let me know how to block this message in o365 and what are the  preventive steps? Thanks.


Note- please help me how to block - we have o365
I want to know about email spoof.
For example , I know that we can verify an email is spoofed or not by SPF.
But using ,we can know it is spoofed mail, but it goes into inbox.
Why it is not filter by spam-filter?
Thank you.
Phishing scam: "Pending message"- how to set my sonic wall for such type of email. We have O365 email system. Thanks
I have a client that sends invoices through Netsuite. The clients domain uses SPF, DKIM, and DMARC. Their DMARC policy is: (v=DMARC1;p=reject;aspf=r;

When emailing certain customers they get bouncebacks and after contacting Rackspace who hosts most of the customers they can't reach. Rackspace is saying it's because of domain alignment under the DMARC standard even though SPF and DKIM match fine. (After I finally reached someone who understood what DMARC was and didn't want me to add Rackspace to our SPF...)

The headers on the netsuite include the following bits which some or all are apparently the cause because they specify netsuite instead of my client's domain so they aren't aligned:
Reply-To: User <>

Spoke with someone at Netsuite who says that Netsuite can't change this behavior at all, but Netsuite also claims they can send DMARC-compliant mail. Is anyone else able to get DMARC working completely with Netsuite?

When the client sends to me on O365 it passes SPF/DKIM/DMARC just fine, but I also see the above bits in the headers. It looks to me like it's doing SPF checks against the domain instead of my client's domain...which seems like Netsuite actually is tagging these wrong...

This is what O365 says in my headers for DKIM/SPF/DMARC …

Exchange  and anti spam(proofpoint) in DMZ.
If I send e-mail to non-existent e-mail address in my organization
I receive error
#550 5.1.1 RESOLVER.ADR.RecipNotFound; not found ##
But if I send e-mail to non-existing e-mail address outside of my organization e.g. Gmail
I dont receive any error in outlook.
Proofpoint logs has error user unknow
sendmail: KCdM73031878: DSN: User unknown
but sender doesnt receive any information in outlook.
Where should I start  troubleshooting  Exchange or anti spam?
Any advice please
Thank you
email that I'm sending is now going to my customers spam boxes.  kinda happened out of the blue.  its not bulk emails.  its individual emails the i type with info for my clients.  i do copy/paste some info that goes into each email as well.

been working fine for years...its just all of the sudden everyone is saying that email is going to their junk boxes.  

its my own private domain email, i use gmail as the client for checking and sending it.

i havent changed anything on my end.  what do I need to look for to see what is going on?  TIA
How to block outgoing SMTP-connections from one IP on a Linux server.

I have a Linux server (Running Plesk) with 2 IP's
IP1 is used for website
IP2 is used for mail

I want to block users from creating script to send mail directly (spam).
All mail are supposed to be send via the mailserver on IP2

In the Plesk Firewall, I can block incoming connections on ex. port 25, but not (as far as I can see) outgoing.

I found this suggestion:
iptables -I OUTPUT -m owner ! --uid-owner postfix -m tcp -p tcp --dport 25 -j REJECT

How can this be done?

ISP LTD magticom, from our server cant sending email to domain, reason :
host []
    SMTP error from remote mail server after end of data:
    550 Mail content denied.
please unblock our server's ip.
thx for cooperation
What were the top attacks of Q1 2018?
What were the top attacks of Q1 2018?

The Threat Lab team analyzes data from WatchGuard’s Firebox Feed, internal and partner threat intelligence, and a research honeynet, to provide insightful analysis about the top threats on the Internet. Check out our Q1 2018 report for smart, practical security advice today!

Hi There,

For the past few weeks users on my network and users they typically email have been complaining about receiving a lot of spam from our users.  I have gone around to every computer and ran malware cleaning tools such as malwarebytes, superantispyware, ccleaner, adwcleaner, antivirus and so on.  I have found many problems and removed them but the spam will stop for a few days then suddenly come back with a ton of emails.  Our email is hosted by an outside company like godaddy and it is pop.  We don't have a good firewall yet so i can't scan the logs of the firewall.  Is there another way to scan the network to detect which pc has the spambot infection and do you know how to remove the virus.
Hello ,

I imagine that if there is a transparent anti spam server works like in a topology as this :

------------->   SERVER BOX ---------------->  Switch ----------------> Hosting / Mail ...etc. servers.

I want to know if there is a software that works without creating config for each domain / mailbox will handle the mails and send to the servers if they are not spam
Hi All,

Could I ask for your recommendations please. I am having lots of problems with loads of spam at the moment on my server.  I used to run AVG on the server but still my clients had far too much spam getting through.  Can you suggest what is best.  I only have a small network of 10 clients and 1 server and limited budget.  Have been attempting to get BitDefender but their customer service is poor at the moment as I have been awaiting a call back for 2 weeks after several chase ups.

Have tried using the spam setting within my Windows setup but changing the setting makes little difference.

Many thanks
Hi, I have a issue. Our WP web server has been compromised and has been infected with a spam-sending virus. We have cleaned the infection but we got to many spamlists including The problem is, that we have never used this server (IP) as a mail server and we are using google services (not only) for emailing. We have made actions to block any smtp traffic from or to our web server. But that aslo means that we are not able to send de-listing email from our  IP.  This is a "catch 22 situation" when we are not able to send mail from that ip but the server still keeps record that we used to spam and some of our customers' mail servers deny our mails as spam because they check our domain IP which ends on this IP... . How to get out of that? Is the only way to start webserver on that IP and send delisting mail? I would really hate to do that...
Can anyone help me in writing a powershell script that will do the following please:-

- Check e-mail server if down then report e-mail server down
- If e-mail server is up then do the following:-
    - send bulk e-mails to users from a csv file - contains the headers (first name, lastname, e-mail) with an attachment file
    - check/confirm e-mails are sent
    - If during the process, e-mails are failed, report this. re-attempt to send failed e-mails up to three times
Dear All Expert,

I have install and configure Zimbra Mail Server already. Now I want to improve security on my Zimbra mail server. I want to make sure my Mail server was protected with spam, so I decide to integrate SPF, Razor and Pyzor but I meet an error after I installed those. After I installed SPF, Razor and Pyzor, the service spamAssassin in zimbra cannot start. It seems the instruction I followed was wrong.

So, Can any one tell me how to integrating SPF, Razor & Pyzor to Zimbra SpamAssassin In Ubuntu 16.04?
I really need your help very urgent.

Regards and Thanks,
Chanveasna Tep.
Is this some kind or email address if so can you tell me who it belongs to and why it showing stuff off of my email and my boyfriend email and what it is and how I can look at the stuff.  The other emails I'm questioning are, , , And
What is the best Spam filter for exchange 2010 which is hosting other companies email domains?
As of Dec 1, 2017, Cloudmark is abandoning their DesktopOne product which was a very good spam filter,  One "Pro" license allows you to configure multiple accounts to filter.  It works by using IMAP to look at messages and leave them alone if not spam, or move them to a spam folder if they ARE spam, so any email account that uses IMAP can be configured.  I have ten or twelve accounts configured.  

There are three criteria I would like to satisfy
1. the application scans email on the mail server using IMAP (as opposed to scanning as the message comes into the email client on the user's computer)
2. it allows for multiple accounts to be configured.
3. it installs on a WIndows machine (this one is negotiable - I don't know Linux that well, but with the right user guide, I can work through it)

I will also entertain offers to have a spam filter "server" built for me

Thank you in advance.
Top Threats of Q1 & How to Defend Against Them
Top Threats of Q1 & How to Defend Against Them

WEBINAR: Join WatchGuard CTO and our Threat Research Team on Aug. 2nd to hear the findings from our Q1 Internet Security Report! Learn more about the top threats detected in the first quarter and how you can defend your business against them!

I host with Blue Host
after I bought on the web
I am getting a non stop barrage of spam from China, Korea, Japan
offering wholesale pricing

I already have a supplier

Does anybody know how I can block incoming spam
based on *.extension or IP range

I cannot keep erasing 10 to 20 spams a day

Thanks !!!!
Hello friends ,

I know it is impossible to give a 100 percent guarantee for that . But is there any to do list for general rules at least to do %80 - 90

For ex.
Mail container's email count per send

Gmail's sensitivity's
Hotmail / outlook sensitivity's
Hello friends we have 20K + public ipv4 and we should be aware of check all ip addresses in all spam lists.

Is there any tool / php script that check all spam lists for all ip addresess and help to remove from them ?
I have a bunch of domains that my office use for their signatures.  For some reason, 1 of them which is fairly new, a year old is causing emails to come back blocked.  I've tried searching the blacklist sites and putting in the domain but they show that everything is fine.
I know for sure Charter, Verizon, and a few others are blocking this, but I'm not sure where to start.  
Just to be clear, the email address isn't being blocked and all is good, but a web link in their signature is causing the email to be blocked.  There is nothing wrong with the link, what's typed is where it's going.


Various techniques are used to prevent email spam (unsolicited bulk email). No technique is a complete solution to the spam problem, and each has trade-offs between incorrectly rejecting legitimate email (false positives) vs. not rejecting all spam (false negatives) - and the associated costs in time and effort. Anti-spam techniques can be broken into four broad categories: those that require actions by individuals, those that can be automated by email administrators, those that can be automated by email senders and those employed by researchers and law enforcement officials.