For all you smart electrical people, I have a question that's picking my brain. I just replaced a light switch with a smart one, and in the process, one of the neutral wires came out of the wirenut (after I turned on the power at the breaker, I noticed none of the outlets worked, so I dug further - tightened the wire nuts much more and solved it). All of the electricity I believe comes in to this light switch box for the room and then goes to the outlets etc. there is no overhead light only lamps, so the switch turns on and off the bottom plug around the room.

The weird thing that I'm confused about is when the neutral wire came out and none of the outlets worked, one of the outlets with a lamp plugged into it came on with the switch off, and stayed on even when the switch was power cycled. When I fixed the neutral wire everything works ok now, but I'm curious as to why this would be.

 

There are circuits in your house called multiwire branch circuits. It's where two circuits share a neutral wire. When you lose a neutral you can pick up power from the second circuit. Sometimes it can be over 120v.

Or.... the receptacle where the light worked was on a different neutral wire in that switch box.

Tightening up a wirenut is not an ideal way to fix a problem. You may have a short wire in the splice that is not making a solid connection.