Has Mailblocks Met Its Match?

I’m a happy subscriber to Mailblocks, an anti-spam solution based on innovative challenge/response technology. When I receive email from an unknown user, the Mailblocks system responds with a challenge message. Humans reply to the message, so their emails get through. The computers sending spam aren’t smart enough to reply, so all those ads for Viagra and penis enlargement never reach me.

Until recently, the Mailblocks solution has been effective. Over the last few months, however, I’ve begun to receive five or six pieces of spam per day: specifically, spam associated with something known as the Nigerian Email Scam. Because the con artists sending these messages are hoping someone will reply to their spam, they receive and reply to the Mailblocks challenge message. As a result, Mailblocks mistakenly accepts their message as legitimate and passes the spam on to me.

I wrote Mailblocks customer support a nice letter about the situation, and was disappointed with their response: “You can block [the spammer’s] address … [or] domain.”

And I can. But as someone paying for a 100% spam-free email service, I shouldn’t have to, should I? Worse, this recommendation is particularly ineffective, since the Nigerian Scam emails never come from the same address twice. Since the scammers usually use free Hotmail or Yahoo! mail accounts to send their messages, blocking those domains would mean blocking email from all legitimate users of those systems.

Rather than note the weakness in the system or explain how Mailblocks plans to address the issue, Customer Service replied with simplistic recommendations that don’t solve the problem and that create more work for me.

I remain a happy Mailblocks user (my article praising the service, in fact, is quoted on the Mailblocks testimonials page). Getting five spam messages a day is certainly better than receiving two hundred — but five spam messages a day is five more than I should receive from a product that claims to block 100% of all spam.

Now that one kind of spam regularly creeps past the Mailblocks filter, how long will it be before others find a way to exploit the same weakness?

It’d be nice to see Customer Support taking a more proactive and customer-focused approach to the problem.