Internet publisher Jenene Crossan's spam horror story is different from the usual complaint of an inbox full of Viagra offers.
Crossan's expensive nightmare began when subscribers to her long-running nzgirl.co.nz website turned on her, clicking the "report as spam" button on their web-based email accounts as nzgirl newsletters arrived.
Enough subscribers hit the spam button to trigger an nzgirl blacklisting by anti-spam monitor Brightmail, the gatekeeper for popular email providers including Xtra and Hotmail.
The ban meant nzgirl's regular mailouts were blocked from reaching all Xtra and Hotmail subscribers, costing the company several thousand dollars in lost advertising revenue over a fortnight.
"[Sponsored mailouts are] a huge part of what we do and to suddenly have them put a restraint on us was incredibly unfair and totally unjustified," Crossan said. "It was pretty big for us."
From an email marketing perspective, Crossan had done everything right. Her emails are only sent to nzgirl website visitors who had actively signed up to receive the regular newsletters, each of which includes clear instructions for unsubscribing.
"It's in our best interest to make sure we don't annoy people. We're a service.
We want to keep people happy, she said. She has a message for "lazy" subscribers who sign up to website mailing lists, then use the "report as spam" option, probably because it is seen as an easier option than unsubscribing: "If you don't want to be on a list any more, unsubscribe. If you have issues over unsubscribing then absolutely flag that [with the company concerned]."
Xtra referred Crossan, and the Herald, to global internet security giant Symantec, which owns Brightmail.
Symantec New Zealand country manager Richard Batchelar said Brightmail blocked mass emails if a high percentage were reported as spam over a set time period.
He said the problem was likely to become more common as businesses sent out increasing numbers of subscriber emails. Brightmail allowed internet service providers such as Xtra to "white-list" known publishers so their emails were not blocked.
InternetNZ councillor David Harris said the problem was common overseas and was often due to malicious users fraudulently signing up to a mailing list under someone else's email address.
Harris recommended publishers use a "double opt-in" process where subscriptions were confirmed by email. "A lot of businesses are frightened by what they perceive as compliance costs with double opt-in, but it's actually nothing more than making a fairly small change to your website and archiving some email."
He said while ISPs might technically be able to reduce the problem, tight margins meant they would be reluctant to commit staff to address this type of issue.
John Schofield of online advertising consultancy The Internet Bureau said New Zealand publishers offered quality content to their subscribers, so it would be unfortunate if this became a wider problem.
"It may even get to the point that publishers need to shift their unsubscribe button right to the very top of their email to make it as easy to unsubscribe as it would be to hit any other button."