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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My friend is using a service called SpamArrest to manage his unruly inbox. Any new senders will receive an email back from the server asking they pass a "capcha" type non-robot test. After that, they're whitelisted and may email freely.

He's moved to Office 365 and SpamArrest isn't compatible.

The goal is a robust email whitelisting cloud service that will work with O365 Exchange and Outlook Desktop Client. Do you know of a product that can meet this need?

Thank you,

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Hi, im deploying Barracuda Cloud Spam, we have Exchange 2016 in house, i believe i have to allow certain IPs from Barracuda, where would i make this change?

We are running an out of warranty MacAfee appliance of secure email.
Now we are looking for a Cloud based solution that scans out email for virus / spam /adware and all other kind of nasty things that does not belong in our network.
We want to have a good control over the spam settings and release spam when there is a false positive to release the mail to the user.
We have 500 emails clients and likely, we are growing so looking for an enterprise solution.
What do you recommend or do you use for your email spam/virus solutions?
Many Thanks.
Hi Folks,

I'm new here. Glad to be a part of this prestigious group. Lately we're observing random spams with below header. Needed some help with improving 365 spam filtering for this case. Thanks, much appreciated. with HTTPS via
 SY3PR01CA0107.AUSPRD01.PROD.OUTLOOK.COM; Thu, 26 Jul 2018 00:03:00 +0000
Received: from (2603:10c6:201:2c::14)
 by (2603:10c6:0:a::17) with Microsoft
 SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id
 15.20.973.21; Thu, 26 Jul 2018 00:02:59 +0000
Received: from
 (2a01:111:f400:7eb5::200) by
 (2603:10c6:201:2c::14) with Microsoft SMTP Server (version=TLS1_2,
 cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.995.16 via Frontend
 Transport; Thu, 26 Jul 2018 00:02:59 +0000
Received: from ( by ( with Microsoft

 SMTP Server (version=TLS1_1, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA_P256)
 id 15.20.995.12 via Frontend Transport; Thu, 26 Jul 2018 00:02:58 +0000
Received: by (Postfix, from userid 2004)      id 5DC7456544; Thu,
 26 Jul 2018 03:02:55 +0300 (EEST)
Received: from localhost (localhost [])      by
 (Postfix) with ESMTP id 4A53656542      for …
User believed that their computer was hacked, and some sort of malware was sending out messages.
They received several phone calls from friends who had gotten blank email messages.

I installed and ran Malwarebytes, which removed 717 components of Potentially Unwanted Programs. McAfee had been previously installed, but that protection didn't notice what Malwarebytes found and quarantined.

I noticed that there was something, possible an extension, that was added onto chrome.  I

Is there anything else that I should run?
What's a good way to check if emails are still being sent out?

Hello I have a user that contacts in their email account is being spammed by a fake email account with their name but not their email account, so I am thinking that if all of the people on the sent list is from this users email contacts and then it list them as the sender it must have something to do with their account?  How is this happening?

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 ?

Looking for a low cost spam filter in an exchange server.  I was wondering if I could use a Ubuntu VM on the Exchange box and if there were some built-in or open source spam solution that I could install on the Ubuntu VM to filter out the SPAM email before passing it along to the Exchange server.
This message is sent to me, from me and on behalf of me. Upon clicking the reply key I see the real sender. I have tried to options and add to the blocked list and also open the blocked content and unsubscribe them (meggannsmith6) to hopefully get them blocked by the actual company with the unsubscribe link.
This person is sending me multiple messages each day in two accounts and I changed the passwords and no luck.
What is the solution?
Hello all,
I have a client that has 50 POP3 email addresses for their 50 computers that is being hosted at and using Outlook 2016 as the email program.
The issue is that one of the POP3 email addresses is suddenly receiving a number of porno spam emails.
The spam filter is set to default and I really don't want to change this since the client is in the medical community so it might reject legitimate emails.
Is there a good spam filter program that we can test on the computer that has the POP3 account on it?
I do NOT want to change the MX record for the domain at all to the spam software company like some of the software wants you to.
Kelly W.
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We will soon be starting a relationship with a company where we will be allowing them to send emails to our customers on our behalf from their mail provider using our domain name. They are using Amazon Ses, and they have asked us to add the domain as an allowed sender in our SPF record. We are going to do this, but I am a little uncomfortable with the risk of any potential Amazon cloud customer having the ability to spoof our domain and pass SPF. Because of this, I am looking into implementing DKIM and having the third party sign their messages with a private key.

I want to implement DKIM for our own domain's email messages as well. I have been reading up on DKIM, but it gets a little confusing when third party senders become involved. I am looking to see if anyone can provide me with a best practice for this situation.  If I create a private/public key pair for our domain, I am guessing that it is not recommended practice to provide that key to the third party and tell them to use the selector name I make up. I have come across different articles describing the use of multiple selectors, but I admit I am finding them confusing. Can I have two different private keys for the same domain? Then I could give them one private key for their emails and have a separate key for our emails? Do I use the same private key, but create two selectors for my domain? Then provide the third party with the private key and tell them to sign using the alternate selector? At that …
Dear Experts

Iam looking for good antivirus/anti spam and other protection software for the recently purchased dell latitude 3940 with windows 10 would like to subscribe for good one can you please suggest which one to go for, thanks in advance. mcafee total protection is slightly cheaper compared to mcafee business security please suggest.
I deleted an important folder and the spam folder. I empty the deleted mail folder. I restored both together in a new folder. Now I have few important messages (10.000) and a mass of spam together (54.000 ).

We have both kaspersky serverside anti spam and EOP. Both only works on recived Items. Is there a way to scan a folder marking spam items and moving them to spam folder?

I tested spambully but it crashes on training.
This question is for the Exchange Admins out there who have experience in dealing with phishing campaigns or malicious emails in general.

When a phishing campaign with malicious links and/or attachments hits your mail servers what are doing to figure out who clicked the links or attachments in said phishing email?

We are using Exchange 2013 CU19 On-Premise , Outlook 2013

Thank you for your time and knowledge!
i am a google adwords customer and have a number of ads setup, each of which directs the "clicker" to one of my website pages. I was testing one of the ads yesterday and found that when I click on it, I am directed to a page that is not remotely associated with my website. It takes me to a page that sells viagra. This happens on all of my computers and all browsers on all of those computers. It even happens on my cell phone. It does not appear to happen to anyone else. I just got off of the phone with Google support and they could not replicate the problem. When anyone there clicked on the ad, the correct page opened. I've had others test it as well and they all get connected to the right page. It appears that it is just me who is having the problem. I downloaded malwarebytes and ran a scan on one of my pcs but nothing was detected.

Any ideas out there about what could be causing this and how I can fix it?

If you google for "Maximo Training" my add should be very near the top of the list. It's "Maximo Training | Training by Maximo Experts | When I click on that add, a page with the correct URL opens but it shows a page for Viagra sales. When I right click the link and choose "open link in an incognito window", the correct page shows up.

I have 2 windows 7 pro PCs and one windows 10 pro PC. As i mentioned, I get the same results on each. Also have the problem on my cell phone.
Dear Experts

Please can someone assist me.

The public IP of my IronPort keeps getting blacklisted.

I have an Exchange 2010 environment with Cisco IronPorts used as my MTAs.

I have attached the error message.

They keep talking about "direct-to-mx".

My send org send connectorThe Error
AV software best compatible with O365. Any suggestion? Local outlook emails? Thanks
1. Is it recommended to have both Windows Defender and
     Symantec EndPoint Protection running at the same time ?

 2. If not, how can I setup my MDT image
    so it does not deploy Windows Defender ?
  ** Windows Server 2012 R2 test domain
  ** Symantec EndPoint Protection deployed
       to Windows 10 Pro client via MDT image
Hi everyone,

I have a simple questions that's been bothering me for a while now. I have a 3rd party Spam Filter connected to my Office 365 Tenant. When an external sender sends me a legit email it is being tagged as a SPAM. My question is when the email passes through the 3rd party spam filter, is the email still going to be scanned by Office 365 EOP once it reaches Microsoft server or will it bypass EOP?
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Our organization is on Exchange 2010 hybrid environment with O365. All incoming mails are directed to an external spam filter organization which delivers to our CAS servers that handles mail. 3 emails were stuck all night into the spam deliver queue unable to deliver these 3 messages to our server, rest of the messages were flowing. On the spam company side, it just shows peer not accepting the message so they kept retrying. In the end we ended up simply rejecting these messages from the external spam filter delivery queue.

I want to investigate the reason to why this email was stuck in the queue for so long and our exchange was not accepting it. It looked legitimate. I am new to exchange learning, what would be the best way to find out the reason and analyze the log once I find them ?

I'm using MailWasherPro and I'm having some problems designating terms to blacklist.

Today, I got spam email from these addresses:

I've tried designating *.******** as a blacklisted address but that doesn't seem to trip the spam "on" for MailWasherPro. And I've had the same situation with other emails that have similar constructions. Some seem to work sometimes but not all the time.

I have a feeling I'm missing something really simple. And maybe it is--for an expert.

Comments? Questions? Solutions?

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
Looking to get exchange documentation for a 2010 environment

There are 2 CAS , and the same are used as HUB Transport Servers

3 Mailboxes, 1 Unified Messanging Role, Have documented through scripting

Use of Ironport C170 , Barracuda Spam Firewall 300 and Enterprise Vault as well

Is there a handy way to check load balancing, I want to see if its set up through CAS Array, whats best way to check this and interaction with Ironport, Barracuda etc to generate mailflow diagrams?
Hi...why all of sudden all my domains are blacklisted in Spamhaus DBL.
This is using MS Exchange Server 2016 antispam features. Although I have run the "install antispam.ps1" successfully. However, spam still rampage. How to configure this features so as spam can be detected and caught in no time?

Thanks in advance.


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.