The sound on my computer stopped working, what’s wrong?
The speakers are connected and it was working fine. I had it on “mute”, when I turned off “mute” I had no response. If anyone can help me I’d really appreciate it. If it makes a difference it’s a Hewlett Packard Pavillion 4455. Thanks. 
try rebooting the computer.
I’ve had this problem from time to time, and what Primaflora says usually works. If it doesn’t, try a complete shutdown (power off). Sometimes a restart alone doesn’t fix it.
I’ve tried both suggestions, neither did the trick. Thanks for trying to help!
When that’s happened to me before, I reinstalled my sound card drivers, and that did the trick. Assuming you use Windows, they should be on the CD somewhere, I believe.
What sounds dont you get, all? You should make sure your volume on both your speakers and your master volume control is up. If you are using a Sound Blaster Live card with the associated software, it has many features that will do that. It has sliders to adjust wav sounds mic sounds, your main sound, cd sound, etc. you should check there and maybe ressetting it to default. And check the one in windows as well.
There are a few places the sound can be adjusted on a computer which is a drag. See if you have a sound thing in the control panel. Im trying to read your mind on what operating system you are using but you’re not coming in clear.