One bank's brilliant upgrade was another bank's crash

who, me? Monday again? It seems like only yesterday it was Sunday. Oh well, that means it's time to kick off the working week with a dose of Who, Me? – The Reg's weekly confessional, where readers share tales of tech mischief and misadventure.

This week, meet a reader we'll Regomize as "Nick" whose career in finance once had him working for "a large US bank in the City" (for non-UK readers, that means the financial district in London).

One of his functions was keeping an eye on market data, which was sent out regularly by services like Reuters among others. These were early days, so the system was not all high-res and fancy like it is now. Users would type into an X-terminal, and Reuters would send its reports in a standard format: 64 columns by 17 rows.

Most importantly, all the banks' systems were standardized on that format, so that as data was sent out everyone could read it with no issues of formatting. You would enter a code for a particular company – say, BP for British Petroleum – and up would come the latest info that the markets might need to know. Not a lot of information fit in a page, but it was functional.

Of course, as we all know, technology inevitably improves with the relentless march of time. And one day Reuters sent out a memo informing users that it was trying out a new format: 80 columns by 25 entire rows. Can you imagine the vast panoramas of data that were promised?

It was, of course, just a beta test, so don't go trying it unless you know your system can handle the new format. You don't want to go crashing your bank's computers, now.

Well, Nick was confident his bank's systems were up to date and bleeding edge, so he went and had a go. He entered BP.L – where the L indicated that he wanted the long form document – and his screen automagically reformatted itself to the new size. Up came a massive page with everything he could want to know. And space for more!

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He showed it to a colleague, who was duly impressed. The colleague suggested he might tell a friend of his, who worked at a different bank. Nick recounted for Who, Me? the half of the conversation he heard:

"Hi there, how are you?"

...

"Hey, have you seen these new large pages from Reuters?"

...

"Well, try typing in BP.L"

...

"Ah. Well, I'd better let you get on then."

It appeared that Nick's colleague's friend at the other bank had not checked first to ensure that the system could handle the new format pages, and had found out – the very hard way – that no, it could not. The system crashed completely.

And Nick's colleague hadn't thought to warn him.

Because Nick hadn't thought to warn him.

Nick never did find out what the consequences were – if any – of the unscheduled downtime. He wasn't game to call and find out.

But to the extent that he bore any responsibility as the instigator of the ill-fated attempt to load a page, he escaped completely scot-free. As Nick put it: "It was Reuters who crashed their system – not us. All we did was load the gun."

You can argue that one in the comments.

If you've ever set in motion a chain of events that led to technological chaos, then escaped even a hint of blame, this is where you can tell all, anonymously, and finally have your evil genius appreciated. Send an email to Who, Me? and we might share it on some future Monday.