No Sound, no audio device, and unknowns

Hello, I own a HP 7915. I recently crashed the system and had to do a system recovery. Afterwards I lost sound. I have seen simialr threads but none of them worked and there is a difference tro my problem that I have not been able to find an answer yet.

I went to sounds and devices and under volume it says No Audio Device.

Under the audio tab in sound playback it says under default device No Playback Device and voice playback it says under default device No Playback Device.

HP says my factory sound hardware is suppose to be Realtek Audio Codec or Creative Audigy, but when I go to the hardware tab it's not in there. There's a list of other devices and underneath it all there are two that says Unknown. I went to properties ansd it says

The drivers for this device are not installed. (Code 28)

To reinstall the drivers for this device, click Reinstall Driver.

I hit the reinstall driver through windows update and it searches and never finds it.

I don't get it. Why aren't the Realtek or Creative in my hardware, what are those unknowns and what should I do with them, and most important I want to get my sound back.