As some of you may know, both of my desktop PCs., were hit by a virus and among many problems, both of them lost the sound. I reformatted them and thanks to Rollin-Again's advice, I was able to fix the problem on one of them (the oldest: Acer 1999) and it was working fine. But following his fine instructions on the new one (Assembled 2005) failed to correct the problem. I called a Technician and he:
1. Unscrewed the lateral lid.
2. Read and wrote the number of the sound card (By Gigabyte).
3. Got into the Internet and downloaded the drivers for the specific model.
And, SHAZAMMM, THE SOUND IS BACK AND WORKING FINE!
Total time invested: 12 minutes.
I relay this information hoping that it might help somebody with the same problem.
Greetings to all and a happy new year to everybody at TECH SUPPORT GUY.