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BEV Email marking and filtering

BEV has implemented an email marking and filtering system for all BEV email accounts. Messages containing certain email attachment types that have been used to spread viruses are blocked, and spam is blocked or marked using SpamAssassin, an open-source program.

Please Note:

BEV cannot guarantee that all viruses will be blocked, or that all spam markings will be accurate. Always use a virus-scanner on your computer, and keep it and your operating system up-to-date. Some spam may not be marked, and some legitimate messages may be marked as spam. We recommend checking marked messages for any false positives. Additionally, this service does not remove spam from your inbox without the use of filters or rules within your email client. For more information on using filters, refer to How can this help me keep spam out of my mailbox? section below.

What email attachments are blocked?

BEV currently blocks all messages containing any of the following file attachment types: BAT, CHM, CMD, COM, CPL, DLL, EML, EXE, JS, JSE, LNK, PIF, REG, SCR, SHS, VB, VBE, VBS, WMF. These file types have been used to spread viruses in the past, and even if you update your virus scanner frequently a brand-new exploit will not be detected. If necessary, you can send one of these file types by using a different file extension. For instance, copy "myprog.exe" to "myprog-exe.new", attach the new file to your message, and in the message text ask the recipient to rename the attached file back to "myprog.exe" after they have received it.

How does Spam Assassin work?

Spam Assassin works by evaluating an email message and assigning it a Spam-Level score based on items such as who it is from, the subject line, and keywords within the message. The higher the score, the more likely a message is spam. Email scoring a 5 or higher arrives in your inbox marked with a subject line that looks like:

Subject: [SPAM?:07.89] Something You Don't Want to Buy

"07.89" is the Spam-Level score assigned to this message.

There will also be a header called "X-Spam-Level". It appears as:

X-Spam-Level: *******

The number of asterisks corresponds with the Spam-Level score reported in the subject of the email. In this case, there are seven asterisks for a score of 07.89.

Will I lose any of my email?

No email is deleted by the Spam Assassin program. Email that scores a very high Spam-Level is automatically rejected by the server. This email is returned to the sender.

How can this help me keep spam out of my mailbox?

You can use the subject line and headers created by Spam Assassin to use filters, or rules, to move your spam into a separate folder, or even straight into the trash. Here are some ways you can filter your marked email:

Filter email if the subject begins with "[SPAM?"
Filter email if the header "X-Spam-Level" contains, for example, "*******". This would filter out all spam with a score of 7 or higher. "**********" would filter out all spam with a score of 10 or higher.

If you are going to set up a filter based on the "X-Spam-Level" and the number of asterisks, keep in mind that most spam will have a score of 5 or higher. We recommend setting up your filter to look for at least 5 asterisks. If you find that looking for 5 asterisks filters out too much legitimate mail, you can change it to a higher number.

For information on setting up rules or filters in your email client, refer to your client's Help documentation.

Why did this message get marked as spam?

If you are curious about why a particular message has been marked as spam, you can find out by looking at the headers of the message. The header "X-Spam-Status" lists the tests used to mark this message as spam. An explanation of what these test do can be found on the Spam Assassin web site.