Anti-Spam

Connection Filtering and RBLs in Exchange 2013

Exchange 2003 and later have included Connection Filtering in its repertoire of built-in anitspam tools. In Exchange 2007 and Exchange 2010, this is implemented using the Connection Filtering agent, a transport agent. Connection Filtering agent offers the following functionality: IP Allow List and IP Block List: Static lists of IP addresses you can populate to […]

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Happy New Year, You Just Won a Gazillion Dollars!

With the end of holidays comes the beginning of a new year, and this year a new decade. I’ve had a longer semi-vacation in December, and I’m looking forward to the promise of an exciting 2011. The part that I least look forward to is all the Christmas/New Year spam, some of which inevitably makes […]

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Released: Exchange Server 2007 Service Pack 3

Close on the heels of Exchange 2010 SP 1 beta, Microsoft has just released Exchange 2007 SP 3. You can download the service pack from the download center. Exchange 2007 SP3 adds compatiblity for Windows Server 2008 R2 to Exchange 2007. With SP3, you can also install Exchange 2007 administration tools on Windows 7 clients. […]

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Social Engineering Attack Disguised As Mailbox Quota Message

Social engineering is all about psychological attacks— convincing a user to willingly divulge information is much more convenient, in most cases, than actually brute-forcing your way in. Attackers with very little technical sophistication (and perhaps some great social skills) can easily prey upon even the more vigilant users. I would’ve held on to my belief […]

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Export and Import Content Filter Words or Phrases

In Exchange 2010 and Exchange 2007, you can add custom words or phrases as good or bad words to modify the Spam Confidence Level (SCL) assigned to messages. Messages with a good word or phrase are assigned an SCL of 0 and bypass other antispam agents that fire after the Content Filtering agent. Messages with […]

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Troubleshooting Exchange Server Antispam: Disable Outlook Junk Mail

When troubleshooting antispam issues, particularly false positives (legitimate email incorrectly tagged as spam), frequently you run into scenarios where Exchange Server antispam features seem to be working correctly but you still see messages being delivered to the Junk Mail folder instead of the Inbox. For instance, you whitelist a sender or sender domain, or add […]

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Disable Antispam agents on a Receive Connector

Exchange 2007’s antispam agents are enabled for all Receive Connectors on a transport server. Is there a way to disable the agents on a particular Receive Connector? Although not as simple as turning an agent off for each IP address or Receive Connector, Exchange 2007’s new transport permissions model allows you to do this just […]

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HOW TO: Prevent annoying spam from your own domain

One of the more annoying types of spam is the one that seems to be coming from your own domain; or worse— from your own email address! Of course, users from your own domain don’t generally spam each other— unless you’re using one of the free web-based email services. And most of us don’t spam […]

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Quarantine Mailbox: Displaying original SCL, sender and recipients

In Exchange Server 2007, messages delivered to the quarantine mailbox show up as DSNs sent by the postmaster address of the default domain. In HOW TO: Expose original senders and recipients of quarantined messages, we modified the QTNE.cfg form for Microsoft Outlook to reveal original senders and recipients. Although the original sender and recipient fields […]

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Exchange Server Antispam Updates: Do I have the latest update?

Not sure if the Exchange 2007 or 2003 (IMF) updates on your system are the latest and greatest? Doubt if the automatic update process is working? You can use the Microsoft Update Catalog web site to search for these. You can also subscribe to the RSS feeds for each update (search result on the web […]

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