I'll bet you a lot of your customers are the same way. I know integrators who are still supporting users running dBase, FoxPro and Clipper applications running on—brace yourself—MS-DOS.

And you know, I don't have any problem with this. You've got an application that's vital to your business that runs only OS/2, fine. If I were your VAR, I'd love to sell you something newer—not to mention more profitable—but I'd also be willing to continue to service your older software and equipment.

Unless, that is, your software or hardware is dangerously obsolete. That's an entirely different kettle of fish.

Delta Air Lines' subsidiary Comair offers a recent example. Comair experienced a meltdown of its crew-scheduling software, SBS International's ancient program Track, during the Christmas holiday.

Comair had to cancel more than a thousand flights—including some from my own hometown of Asheville, N.C.

It was not a happy day at our local airport.

You can't blame the software distributor for this one. The copy of Track that Comair was using was more than a decade old, according to reports. Can you say obsolete?

The specific problem that nailed Comair's software was that it could handle only a bit more than 32,000 changes in a month. Once it went over that hard limit, caused by the use of a 16-bit integer, it was all over with. Days later, Comair was back in the air, but there are tens of thousands of flyers who will now think twice about flying Comair. I should know. I'm one of them.

Let's look at another instance: Windows NT. No, there have not been any recent episodes of NT leaving a ship dead in the water, but NT is officially no longer being fully supported.

Someday, and someday soon, there's going to be a major NT security problem, and Microsoft is not going to be there to bail you out.

The moral of the story is a simple one: You need to get your customers to evaluate their technology.

Yes, most of them don't want to do it. At all too many businesses, CIOs have become flunkies to the chief financial officer. And CFOs see IT as merely a cost center and not as the viable heart of their business.

Heck, do you think Comair's executive staff ever thought of their software, and crew-scheduling software of all things, as being absolutely essential to their business? I doubt it.

So it is that you need to look carefully at your customers' real IT needs. Are they using hard drives without proper backups that are well beyond their MTBF (Mean Time between Failures)? Are they using 8-bit or 16-bit software for jobs that have grown well beyond their original limits? Is there still a software vendor that stands behind their mainstay programs?

If they are, and they're not willing to spend the money to upgrade their technology, you might want to consider waving good-bye to them. Sooner or later, they're going to have a complete failure, and I, for one, as the IT expert, don't want to get blamed for their penny-wise, pound-foolish approach to IT.

eWEEK.com Senior Editor Steven J. Vaughan-Nichols has been using and writing about operating systems since the late '80s and thinks he may just have learned something about them along the way.

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