No Audio Output Is Installed please help!

Hello,

I have the problem where I woke up a couple days ago and all of the sudden my sound is not working on my laptop when it was the day before. It says "No Audio Output Is Installed". I literally have tried just about EVERYTHING there is to try and get this to work.

I have an Acer Aspire 4330. Built in speakers. Realtek High Definition Audio sound card. I have Vista Home Basic. SP2, which I upgrade to a couple days ago to see if it would fix my problem but it didn't.

Here is the list of what I have done to try and fix it.

1. Uninstalling the driver from the device manager and then reboot to get it back, when rebooted, the installer says it failed to install.

2. Upgrading the driver, when I do this, it says I have already updated to the latest driver when in fact the sound doesn't work.

3. Sometimes when I try to upgrade the driver again it gives me another message saying cannot install, it may have been corrupted or missing(code39).

4. System restore

5. Uninstalled the driver from add/remove programs. All that did was remove "Realtek" from the sentence and it just left "High Definition Audio in the device manager.

6. Downloaded and installed once again the Realtek's driver from Realtek's site, so now "Realtek is back with "High Definition Audio" part.

7. I have upgraded to SP2 a couple days ago as said before, no luck.

8. I've tried rolling back the driver and then upgrading it and no luck.

9. I've went to the BIOS and there isn't even anything about Realtek anything except the boot order but that's not related to my problem.

10. I've typed in "services.msc" in run, and then went to "Windows Audio" and tried to enable it. But it was already enabled and set to automatic.

11. I went into safe mode and done virus and malware scans, no infections.

12. I have went into the registry and deleted the upper and lower filters because of code 39. No luck

13. I have done the fix it for me thing from microsoft and no luck.

Please help if you have any other suggestions than what I have put, or just a hunch, please reply....I would be so greatful, it seems that nothing has worked. Microsoft said that this happens if I just came out of sleep mode or hibernation mode which I do frequently, but I wasn't home when this happened. My cousins and bro was playing the computer when in the middle of playing they said it stopped working. My bro said it was working when he was playing it and then when it was my cousin's turn to play he said it wasn't working.