Kia Sportage problem with power windows and door locks

Help, my daughter has a 2001 Kia Sportage. The vehicle is 4-Wheel Drive, with about 10300 miles on it. The vehicle’s power door locks and windows, all four have stopped working. Took the car in today for a new muffler and the mechanic indicated he’s not sure what it is. So far he has checked the door switch and the doors are getting power. I checked the fuses and rely and those are ok. Does anyone have an idea as to what could be wrong???

What does it mean to say that the doors are getting power? Are you sure that the door switch itself was checked? Or was it the wiring to the switches? If so, and if that voltage was correct, then I would guess the switch panel is bad. You can probably find one at a salvage yard for not very much. Not much else would make sense for all of those things to have stopped working - unless they all stopped working slowly over time, and at different times.

All four, power doors and windows are affected. None of them work. The mechanic focused solely on the drivers side door. He told me the switch was getting power and he further indicated he checked the wiring. They found one (a switch) at a salvage place for $100. but he indicated that was not the problem. It happened slowly over time, but my daughter indicated that when they stopped they stopped all at once and none of the windows roll down.
She has a keyless entry device for the vechicle, which stopped working could this have anything to do with the malfunction??? The mechanic said it might be the motor inside the door. But would all four doors be affected?