1998 Ford Taurus door ajar

Typical Taurus problem. Use some WD40 and spray it in the door latch. Open and close the door several times. Spray more WD40 in it every 5 or so door closes. If the light still stays on, move on to the next door. Start at the drivers door. When you find the right door causing the problem, go ahead and do the same to the rest of the doors. You may have to open and close the door(s) many-many times to get the light out. But, it will go out.