Question : Problem: No sound after turn off the computer

I got windows xp pro sp2, and my pc is Emachine 2682 with Ac97 driver, no sound card; no disk installation. The software came with the pc. I do know what happend but no more sound in my pc. After download the driver from Emachine web site and install it' works fine; but after turn off the pc and and turn the pc on again the sound doesn't work still. I have done this lots of time but still no result. How can I make the sound work on my pc again?
P.S the only difference is that I get a screen that dosen't let me enter to see my device manager (date Execution Prevention. Run a DLL as an App) after my last windows xp update .

Answer : Problem: No sound after turn off the computer

either try system restore, and restore to the state before you ran windowsupdate; or open add/remove programs, have checked "show updates", and uninstall updates.