I guessed it was probably Windows but I've learnt from doing help desk NEVER assume anything. I had some aircraft engineers who phoned up to say "every time we switch on the kettle the PC goes off". After quite some time we worked out they were pulling out a plug (the PC) to then plug in the kettle! They didn't associate one action with the other and these guys repaired 747s! Another person had their PC fail. Me: You have a backup? Them: Yes. Me: You should be OK then. Went to their desk, rebuilt the PC then asked for the back (floppy) disks. Was handed one. Me: Where are the others? Them: That is it, when I did the backup it would eject the disk and then say put in a floppy disk so I put it back in....". Me: <silent> but thinking "your F***ed". Also, saw a mainframe fry because wine was poured into it. It was Christmas and we were playing volleyball over it and someone had put a bottle of wine on the top which inevitably got knocked over.... In another company, the mainframe room had carpet tiles but every so often one would go missing (because it was damaged and was a trip hazard) so got replaced. Went round to a guy who I worked with and found the living room carpeted with tiles from the mainframe suit. Also had a full set of cutlery from the canteen along with salt and pepper. The joys of the IT department. But I digress.
Have to disagree about Windows. I like 7 and 8 and have had no issues with both OSes. Problems have been with hardware and or the operator doing something stupid. My windows 7 server box has an up time of over three months now with the only down time being for reboots after updates.