My computer has lost all sound. I have no clue how

This is HP Support, and the Software and Drivers page for the Pavilion a867c Desktop computer, utilizing Windows XP;

http://h10025.www1.hp.com/ewfrf/wc/softwareList?os=228&lc=en&dlc=en&cc=us&product=448709&lang=en

1.Under the Driver - Audio heading, Left-click right on the words -
Realtek High Definition Audio Driver Update (in blue)

2.You'll be directed to another page. On this page at the top Left-click on -sp26552.exe, (1/1, 13.07M)

3.A small window will come up. Left-click on - Save File

4.You may or may not see a download progress bar. If you do not, give it 30 to 40 seconds to download. It is a 13.1 MB file in size.

If you do not have your downloads set to save to your My Documents folder, this file will be saved to your desktop screen. (Start>My Documents)

Close all windows, (Internet), go back to your desktop screen.
In either place Desktop screen, or My Documents,
when you see the file, Double-click right on the file name.

(sp26552.exe, under a blue square with 2 triangles in it)


Now the Installation Wizard will come up, and lead you through installation with simple instructions. (Just click on Next, Next, and Finish)

u will need to reinstall your audio driver u can get this from your computer Mfg web site under support driver downloads. or you can try to rollback the driver from the device manager menu "Start right click computer select properties select hardware then device manager then select sound and video controller find you audio driver and double click and select roll back if this does not work refer to the first step reinstall driver from mfg website hope this helps