Ceiling light used to work. Changed fixture. Seems no power is coming through wire.?

I have recessed lights in my ceiling. I have had to replace these every now and again. For some reason they keep blowing out. I had another stop working, so I removed the light bulb, and put it in another fixture. The bulb works so I figure the fixture must be messed up. I replaced the fixture, and found that for some reason I no longer have power in the wire that went to this fixture. I have no idea where the wire comes from as it is inside the ceiling. I installed the fixture in another location and it works fine. So I have narrowed the problem to this specific wire. The light fixture used to work...The fixture is on a switch with all of the other lights in the ceiling. The other lights all work.