I connected a computer speaker to my HP 620 Dual Core computer. After removing it back, the sound is not coming from the computer anymore. But when I connect it with headphone or external speakers it comes.
Right-click on the speaker icon in the notification area. Select 'playback devices'. Select what you want to be your default playback device.
Control panel and check it dude...
Go to: Start>> Control Panel>> Sounds and Audio Device Properties.
Be sure that the "Mute" checkbox is unchecked
uninstal audio driver reboot and let windows to reinstal a new one.
just plug in the headphone a bunch of times and wait for 30 seconds to see if the speakers will function, possible you removed it in wrong way so something went wrong with windows driver detection.
If you want to manually move the audio, you can do so in the control panel. Here are instructions:
1) right-click on the volume icon and choose playback devices
2) right-click on the device you want audio going to and choose Set As Default Device
Microsoft Fix it