Spam solutions that avoid (silently dropped) false positives?

July 13, 2015 10:47 AM

Sudden drastic surge in spam to my primary email address, that has lasted a month at the same steady intensity. Time for me to finally consider server-level spam filtering? The catch: my FIRST priority is avoiding false positives.

I often get emails from random strangers that are really valuable and time-sensitive (sometimes with clasically spammy subject lines such as "Congratulations" or "Proposal" or "Hi " -- and from many different countries).

In the past I've gotten so little spam that it's been fine to do NO spam filtering at the server level. (I've just filtered with manually-created local rules in my mail client, which is Apple Mail.)

Now, I'm suddenly getting so much spam that I can't stem the tide with local filtering because the content and the reported senders are so diverse. I can't find commonalities among them (even if it's a single prolific spammer, the actual machines sending are distributed around the world) and they're all addressed directly to me and no one else.

(My address clearly just found its way into really active hands, after years of good luck [the address is available in clear text in various places online, but that's been true for years with no ill effects]. I just suddenly leaped from my usual 5-10 spams a day to hundreds a day. I do nothing to encourage this to continue, afaik; I turn off my internet connection before doing anything that might cause any of them to be reported back as opened.)

So what could I try?

Out of the question are:
• solutions that cause ANY email to be silently dropped at the server level so I never know it existed (suspected spam could show up in my local client with a modified subject line, but every message must show up);
• solutions that mandate any further action on the sender's part (people who email me getting an auto-response saying they must "verify" themselves);
• any google services, paid or free (I'm just not interested in google).

The address in question is my primary address, at my own domain; I don't want to change it. I'm not attached to my current host and I'd be happy to move to another. (They're hosting both that domain's web content and its email addresses, but I'd be fine with switching my email hosting to a dedicated service that just hosts email.) I'm expecting to pay -- not looking for a free service.

posted by kalapierson to Computers & Internet (4 answers total)

Best answer: You might try SpamSieve, a Bayesian filter plugin for Apple Mail. It doesn't take long to train it, and because it runs on the client side it won't delete mail before you can go through your local spam folder. You can also train it to accept false positives as non-spam. I've been using it for years.
posted by Johnny Wallflower at 1:24 PM on July 13, 2015

I don't have personal experience with it but a sibling organization of mine at work uses Symantec MessageLabs to provide anti-spam/malware to a gigantic Fortune 50 company that you've heard of. From what I know of how the solution works, you would keep your existing hosting arrangement but the MX records for your domains would point to the Symantec servers. The Symantec servers would then in turn forward the safe mail to your host when you would access it as you do today.
posted by mmascolino at 1:41 PM on July 13, 2015

Talk to your hosting company they should be able to crank up the spam block.
You might take your email hosting elsewhere. For example Google or MS Office 365 Exchange.
posted by Mac-Expert at 11:37 PM on July 13, 2015

Mod note: Final update from the OP:

SpamSieve has been brilliant and was precisely what this situation called for. Thanks so much, Johnny Wallflower!

posted by LobsterMitten (staff) at 8:49 AM on June 28, 2017