I replaced a flood light lightbulb in recessed light fixture, thinking the previous bulb had burned out, but that new bulb isn't working either. I've tried a regular lamp bulb to ensure my new floodlight bulb was actually "good" and I checked the fuse board to make sure that outlet hadn't been tripped. What other reasons would the light not turn on? the house is only 10 years old and there's no evident damage or anything wrong with the wiring in the recessed lighting.
Test the switch. If you don't have a meter, bypass the switch (line to load). If that doesn't work, you might have a short in a box.