Years ago I worked on a stock control system for a popular clothes retailer. Where previously store managers had to spend hours on the phone ringing the depots to see what was in stock and reordering popular lines, now they could fill in orders an they would be emailed to the depots in machine readable format, with the order balanced across multiple depots depending on availability of stock.
After the system had been in operation for a year or so, managers started to complain that some orders weren’t turning up. After a bit of digging it only seemed to affect one particular depot, but I couldn’t initially see a common factor between the orders. It had nothing to do with the size of the mail, or the originating store. I could tell from the logs the emails were being formatted and supposedly sent to the depot, yet they never translated into orders. The system would silently fail after we’d handed the email to the depot with no obvious reason why.
So I wrote a quick script to collect all the orders for a day from all the stores and compile a list of all product lines that were present in the orders that went missing, but not present in the orders that succeeded, just to see if there was a pattern. This turned up a few dozen items and after a quick visual scan of the product descriptions one stood out slightly, so I phoned the depot on a hunch.
The depot had an anti-spam filter on incoming emails that silently dropped messages with pornographic words in the body or any attachments. The retailer had just received a new seasonal product line, which was selling well, and the product description was “bondage tights”.
After getting the depot to whitelist emails from our system, orders for this product line started working.
Our neighbor, who started as an elementary school teacher but moved into elementary computer education (a roving teacher with an Apple computer lab cart) had a similar problem. Her title had been changed to something like Computer Education Specialist and her email would be blocked when sending to certain other government entities. When the school district upgraded their spam filter, her emails started to be blocked within the district as well. It turns out her title was being identified as Computer Education Spe CIALIS t.
We ran into a similar but much easier to identify problem with PayPal - any products we sold containing the words "Cuba" or "Havana" in their title or metadata, regardless of the context, would cause PayPal to reject the entire payment with a meaningless error and no indication of what had caused the problem.
PayPal refused to admit to us that this was the cause and insisted they couldn't shed any further light on the issue despite the fact we could trigger it 100% of the time.
In the last few weeks it's started randomly choking on the word "Pharaoh", God knows why, and God knows why it only does so about half the time, but I'm not going to bother asking PayPal about it.
Fraud detection and compliance systems have a false positive rate, unfortunately. And a company confirming something like that would be tantamount to telling how to avoid the filter, which also raises their false negative rate, which is not in the company's interest, whether the party in question is a fraudster using it for their own interest or a non-fraudster that spills the beans on HN.
But yeah, it sucks that their system can't learn to give you an exception after it has been reviewed once or twice.
Years ago I worked on a stock control system for a popular clothes retailer. Where previously store managers had to spend hours on the phone ringing the depots to see what was in stock and reordering popular lines, now they could fill in orders an they would be emailed to the depots in machine readable format, with the order balanced across multiple depots depending on availability of stock.
After the system had been in operation for a year or so, managers started to complain that some orders weren’t turning up. After a bit of digging it only seemed to affect one particular depot, but I couldn’t initially see a common factor between the orders. It had nothing to do with the size of the mail, or the originating store. I could tell from the logs the emails were being formatted and supposedly sent to the depot, yet they never translated into orders. The system would silently fail after we’d handed the email to the depot with no obvious reason why.
So I wrote a quick script to collect all the orders for a day from all the stores and compile a list of all product lines that were present in the orders that went missing, but not present in the orders that succeeded, just to see if there was a pattern. This turned up a few dozen items and after a quick visual scan of the product descriptions one stood out slightly, so I phoned the depot on a hunch.
The depot had an anti-spam filter on incoming emails that silently dropped messages with pornographic words in the body or any attachments. The retailer had just received a new seasonal product line, which was selling well, and the product description was “bondage tights”.
After getting the depot to whitelist emails from our system, orders for this product line started working.