I had a 40 amp circuit breaker trip and then when I tried to reset it, it wouldn't reset. I replaced the 40 amp circuit breaker, but now two light switches for the laundry room and furnace room won't turn on. On that circuit there is two downstairs lights (bedroom & hall) and there is the t.v. and a lamp upstairs. After replacing the c.breaker only the two light switches didn't work.
Any suggestions; I'm thinking that there might have been a surge which is the reason the c.b. needed replacing and it went back to the light receptacles and possibly damaged them as well.
Not sure, thanks for any suggestions.

Why in heaven's name are using a 40 amp breaker?

What you are describing is a circuit where a 15 or 20 amp circuit should be.

Can you please give us a better description of this circuit as well as the distance involved from end to end and the load that is on the circuit.

I'm only using a 40 amp breaker because that was what was in the panel when we bought the place 4 years ago.
What is on the circuit is one floor lamp (upstairs), flat screen t.v. with electronic components (stereo)(upstairs), 1 ceiling light bedroom (downstairs), 1 fluorescent light, furnace room, 2 fluorescent lights, laundry room.
The run is approximately 50 - 75 feet long.
I have replaced the breaker with another (new) 40 amp breaker and the bedroom and laundry room were on. Then the breaker tripped and I reset it and the laundry light was on, but when I turned the furnace light on it tripped the breaker. I tried to reset it, but it wouldn't go on.
I am confused because I don't I'm overloading the circuit with just a few items connected to this breaker.
The rest of the panel consists of 15 and 30 amp breakers.

The problem is that, in my thought process anyway, your are using a circuit that at best should be not greater than 20 Amp.

Two immediate problems:

1) If the 40 Amp breaker is protecting an actual 20 circuit, you have a serious fire hazard.

2) If you are using a 40 amp feed to this circuit it is much more than you need.

Have you considered calling a licensed electrician just to get your Main Service Panel sorted out.

Don, I appreciate your advise and I am going to arrange for a licensed electrician to check out panel.

Thank you