The Dark Side of Spam Filtering

I discovered today that several important e-mails addressed to me over the past couple of weeks had been blocked by our spam filter at work. The person writing them had the word ‘free’ in a line of her signature, advertising a free seminar her company is offering. That plus html formatting was enough to trigger the filter threshold. I had to scramble quite a bit today to make up for the delay in getting the information.

There are a couple issues here. One, I need to talk to our admins about raising that threshold a bit. I’d rather get some spam and all of my genuine mail rather than no spam and not all the valid stuff. I may also start sending domains to the network admin that I want added to the whitelist so I don’t lose stuff like this in the future.

I wonder what else I may not have been receiving? There is no easy way in our current system at work for me to review what messages have been blocked. My spam blocking at home works great since I can see exactly what has been filtered out at will.

Comments

Anders Jacobsen
Ouch; that hurts. I definitely prefer to be in the “driving seat” of my spam filtering and having the possibility to do individual whitelisting and tuning of other parameters (although I must admit that after seeing how flawlessly Spam Assassin worked for me; I’ve become lazy and now I don’t check the “spam” mailbox any more… if someone sends me a “spamlike” email and expect a reply, they’ll have to call me to follow up. Call me lazy, but I’m not sure I’ll change anytime soon…

March 26th, 2003 at 6:28 am
andersja's blog
The dark side of spam filtering
Call me lazy, but seeing the way things are developing online, telephone and instant messaging is the way to reach me; there’s just too much spam-email…

March 26th, 2003 at 6:45 am
Eileen Lewis
Using an anti-spam program at the corporate level does require a lot of fine-tuning and will never be 100% accurate. ( no spam in, no legitimate e-mails blocked) The bright side is they can be fine-tuned, it just takes some time. The really darker side is trying to get mail through to other mail systems who subscribe to certain rbls. There are a couple of places we cannot send mail to because their service blocks a whole range of addresses owned by UUNet due to excessive spammers using those addresses. Our association’s address is in that range.
A suggestion- don’t ever use the word “free” in the subject line when sending mail out.

March 26th, 2003 at 8:37 am
David
Thanks for the comments! I let the person who was sending the messages know what aspects of her e-mail triggered the filters. (Yet another reason to send only text messages.)

Another point, that Anders raised, is that we should have resorted to phone calls much sooner than we did. Lesson learned.

Damn spammers.

March 26th, 2003 at 8:44 am
Eric
What spam filter does your company use?

April 1st, 2003 at 1:33 pm
David
Not sure. I’ll ask next time I’m down that way. We have Groupwise for our mail server/client and it may be an add-on product for that.

April 2nd, 2003 at 1:35 pm