We are replacing 3 light older switches in one box.Each switch controls a different light.When we put in the new switches,none of the lights worked.What did we do wrong?
Thanks!
MJD

Well, tell us how many wires and what color are in the switch box.
A picture would be nice.

Hard to tell without seeing how the box was wired, but you most likely misconnected a power lead that supplies the power to the box. You could have used a retasked white wire, unmarked, as a neutral. You will need to find the hot lead and start from there. How many black and white wires are in the box. Any red?

Did you rake all three switches out then rewire in the new switches or rewire ech new switch one at a time?
Did you turn the breaker off before wiring?