No sound at all

Hello,
My laptop is a Dell, it is not very old but im not sure what model it is. The other day i installed a Live! cam video IM pro web cam by creative to my laptop. It has a built in microphone and works with all programmes. It is compatable with my laptop in every way. However when it came to installing it, i was asked questions about the micro phone i plugged it in and installed it. After i realised i could hear no sound. I only heard a beeping noise when i pressed a key or clicked on something that didnt work. I cant hear any sound through the headset, through the laptop itself or through my ipod headphones i used to use. I unistalled the web cam completely bu the problem was not solved, so i reinstalled hoping to change the settings, this didnt work as no other settings were avalible aart from the previous ones. I went to start>control panel>sounds, speech and audio devices>ajust the systems sound voloume and it is on full and not muted but i cant adjust it as it says no sound audio so the buttons are faded and unusable. I dont understand why it says this, as it usually does work. I still can hear no sound at all! I have gone on to the manager settings and seen the sound card files, it says they are working and no need to troubledshoot. It say that all hard ware is correct and working.
When i tried to watch a episode or listen to music it appears to be playing but i cannot hear the sound, i pressed the Fn button on my key board and the Page up button which turns up the volume usually and the tab appears with a bar and i continue to puss the buttons together but the tap is empty, usually if goes up in tiny movements in blue where as now its just staying empty. But through all this there is no errors, nothing is muted, the hardware is fine and there are no error reports or anything when trying to listen to something. I have tried everything and unistalled the camera again, i will not install the camera again but ven without it there still is no sound, i dont understand can any one help?
Any suggestions, thanks.