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AntiSpam

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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Hi Experts, AFAIK there are 3 ways to anti-spam to an Exchange 2016 environment: SPF, DKIM and DMARC

I can configured SPF record on domain control panel but not sure about the 2 others, does anyone have experience with them? Can we configure them on Exchange mailbox server, or public DNS of ISP?

Many thanks in advance,
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When we send an email through our company it is very commonly flagged as junk by the recipient. Can this be fixed? What do i need to do to fix this? We're using exchange from our own in house server. No we dont mass email people. We have never been hacked and used as a bot that im aware of.  Our in coming does go through an online spam filter.
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Hi,

We are using ESAT spam filter and we have a user that is getting spam reports with duplicate emails in them.  

eg.

email is caught in spam filter, it is in the spam report that the user gets
- user retrieves email from the filter
- he gets the email

Next spam report, the same email is in there but the person did not send the email again since it is exactly the same

Has anyone used this spam filter program?

Thanks
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Hi

I have a setup with SpamAssassin, postfix, dovecot and a few other components.
I've set up user_preferences, so they are now loaded from mysql db using the user_scores_dsn etc. settings.

I have created a table in mysql for local Rules (header, body etc) and included them in the user-preferences lookup.
However - I cannot get them to work.

I have added the allow_user_rules and set it to 1.

This is my database connection settings:
allow_user_rules 1
user_scores_dsn                  DBI:mysql:mail:db-server:3306
user_scores_sql_password         <left out>
user_scores_sql_username         mail
user_scores_sql_custom_query     SELECT preference, value FROM spamassassin WHERE username = '$GLOBAL' OR username = CONCAT('%',_DOMAIN_) OR username = _USERNAME_ ORDER BY username ASC, priority asc

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this query returns something like this:
Preference column:
  • use_bayes
  • bayes_auto_learn
  • blacklist_from
  • header LOCAL_H_FORBIDDEN_WORDS_SUBJ_SEX
  • score LOCAL_H_FORBIDDEN_WORDS_SUBJ_SEX
  • describe LOCAL_H_FORBIDDEN_WORDS_SUBJ_SEX

with corresponding values in the value column:
  • 1
  • 1
  • *@bejoqq.org
  • Subject =~ /sex/i
  • 4
  • Bad Word

Is there anyway to have all my rules stored in my database?
It's much easier to maintain her accross multiple servers etc.
0
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
0
Hi All ,

Quiet frequently I'm getting below mentioned error on my barracuda spam filter on out queue mails . The error message is

 "Deferred: conversation with 192.168.77.189[192.168.77.189] timed out while sending message body" .
 
192.168.77.189 is NLB interface of my 2 CAS servers (Exchange 2013 on server 2012 ) . Some days the queue goes up-to 300 mails and goes off in 1-2 hours by itself .

communication between barracuda and the cas server is stable .i couldn't figure out the issue yet . I have contacted barracuda support and they asked me to contact MS as its an issue with the exchange side. can somebody help me out to resolve this issue .

regards,
Sharaf
barracuda.jpg
0
Hello Everyone,

Recent days we are witnessing lot of spoof emails coming into our organization. Attackers used to change 'display name' of the sender so that it look like valid email address. But when analyzing the headers it clearly shows its coming form private domains. Is there any way to block this behavior in Exchange 2013?

Thanks in advance
0
Dear Experts,

My clients and I tried to send emails to proofpoint customers but they get deferred or delayed.

I have done a blacklist check and our IP address is not blacklisted.

Is there anyway to contact proofpoint and inform them about this and get it resolved?
0
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
0
Hi Guys,

We recently acquired the Antispam (CASS2.0) for SonicWall TZ400.
The feature has been installed and configured, but not yet enabled.

I just need some basic understanding and information from someone re the TZ400 Antispam feature.

1.  Our mail does not currently spool via the TZ400 router, it comes via another gateway.   I gather that we have to change our MX to route mail via the TZ400 for the antispam feature to work?

2.  Once mail packets pass via the SonicWall router, will the TZ400 pick up the mail traffic from the NAT rule for port 25 automatically?

3.  We will be using the current gateway as secondary MX (fail-over).  Any other suggestions regarding the config and first hand experience?
0
Cyber Threats to Small Businesses (Part 1)
Cyber Threats to Small Businesses (Part 1)

This past May, Webroot surveyed more than 600 IT decision-makers at medium-sized companies to see how these small businesses perceived new threats facing their organizations.  Read what Webroot CISO, Gary Hayslip, has to say about the survey in part 1 of this 2-part blog series.

I am at wit's end with something that I cannon understand is happening.

My boss signed -up for a newsletter from a website called "fisherynation.com". This news sites send several email out per day and they will not go into my bosses Outlook 2016 Inbox but rather to the Junk-Email folder. Here are the steps I have taken:
- In Junk Email Options, set to "No Automatic Filtering"
- Added fisherynation.com domain to "Safe Senders List"
- In Outlook Web Access (OWA) under setting for "Block or Allow" is set this to: "Don't move email to my Junk Email Folder"
- In Exchange Administration, Mail Flow.. I created a "Bypass spam filtering" for the sender of the emails in question.

Noe of this works! This particular sender of email is the "one and on;y" emails to go into his Junk Email folder. nothing at all besides.

Maybe this is a bug in Outlook 2016? Any ideas anyone?

Sincerely,
Steve
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Hi, I have a justspam.org 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 justspam.org. 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 justpam.org 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...
0
Some (not all) spam emails are not detected by the DNSBL filter.
In the hMailServer log I can see:
DNS lookup: 200.197.98.172.zen.spamhaus.org, 0 addresses found: (none), Match: False

But, if I try to execute the following command:
host 200.197.98.172.zen.spamhaus.org
it does return a match:
200.197.98.172.zen.spamhaus.org has address 127.0.0.3

The hMailServer's spamhaus entry is configured as follows:
<DNSBlackList Name="zen.spamhaus.org" Score="3" RejectMessage="Rejected by Spamhaus." Active="1" ExpectedResult="127.0.0.2-7"/>

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We are using local Windows Server DNS service for caching and I can't find the missed DNS requests in the cache.

How that could be fixed?
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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
0
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.
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O8EKCO@itlgopk.uk
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 krystalmiller685@yahoo.com, jlee551311@yahoo.com , leej8286@gmail.com , krystalmiller457@gmail.com. And ljohn481@yahoo.com
0
What is the best Spam filter for exchange 2010 which is hosting other companies email domains?
0
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.
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I host with Blue Host
after I bought   www.seattlesurveillance.com 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 xxx.xxx.xxx

I cannot keep erasing 10 to 20 spams a day


Thanks !!!!
0
Are You Ready for GDPR?
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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.
SPF
Dkim
rdns
Mail container's email count per send

Gmail's sensitivity's
Hotmail / outlook sensitivity's
....
etc
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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 ?
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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.
0

AntiSpam

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.