I have no sound on my computer\r\ni had sound the

Roll back your sound drivers (control panel, system, hardware, device manager, sound and audio devices, right click your sound hardware, properties, drivers), if this fixes the issue go to microsoft update, run the 'custom' scan...it should show you an update to your sound card/hardware, click the little "+" sign beside the update and click the little "Do not show this update again" checkbox. This will prevent automatic updates from "fixing" your drivers. Occasionally Microsoft sends out updates that are incompatible with a particular machines' setup.
Hope it helps.

Plug in ONLY the regular wired speakers and ONLY to the green port on the back.

Make sure they are powered up and the volume is about half way.

Ok now you need to call up ether the sound card application or preferably the windows volume control from the bottom toolbar.

Click Open Volume Control.

A box with sliders in should appear. make sure that volume control, wave, sw synth, aux, cd player, line in
are all about half way and that none of them have ticks in the box at the bottom.

If any of those are missing click options then properties from the top left and put a tick besides any that were missing (nothing else)
Now close the slider box.

Put a normal music cd in your cd/dvd player on the computer and set it to play with windows media player.
You should now have sound out of the speakers.

Double check that EVERYTHING is ok.
If there is still no sound check the control panle for any hardware issues and rectify those with the correct drivers