The help desk must be a miserable place to work these days. According to our InformationWeek Analytics OS Wars Survey, nearly every company supports Windows, half of those polled officially support Apple devices, and three in 10 support Linux or Android operating systems. Two-thirds of companies let employees connect their personal gadgets to the network with little or no guidance as to what devices and operating systems they can use or whether IT's supposed to help them. If anything goes wrong, you know who gets the call.

Welcome to the OS mess.

Windows still dominates, showing up in 99% of responses, but that dominance masks a huge change in the number of operating systems IT is dealing with. Eighty-five percent of IT organizations officially support more than one OS; the average company supports three different ones. Smartphones are a major force, ushering in Apple's iOS and the Linux-based Android on a large scale. But our research shows broadening OS support across all hardware platforms, including servers, desktops, laptops, tablets, thin clients, and smartphones.

And that's just the official count.