Lost Realtek AC’97 with Error Code 10

After installing Windows 7 on my computer, I lost my Realtek AC’97 with Error Code 10 and in my device manager; a yellow exclamation mark keeps appearing next to it. I own an Intel Premier P4 32-Bit 2 GB.
I contacted the manufacturer’s site but they went out of business. So, I visited Realtek’s site and downloaded the newest driver update but still didn’t work. Also, on the bottom right corner of my screen, the speaker symbol is marked with a red cross. What does this mean? Can anyone please help me in solving this issue? Thanks a bunch to those who can help.
