Hello,
I replaced two ceiling fixtures on our second floor. I Checked that each worked before completely securing to ceiling and they did. So upon checking the final light before securing (it worked as I said), I then flipped the master breaker off again to finish up(fyi- we have an old fuse panel not a breaker panel). When I turned it back on , the light no longer worked and now none of the lights on that same fuse work! I thought maybe a connection came loose so I undid both lights (which looked fine) and still no luck. The fuse is good still as I swaped it with another I knew worked. Any ideas of what's going on here?

A Look is only good if u checked to see if the wires inside the wire nut where connected together. It is possible that the wire nut looks good but the wires are not connected.

Chuck