No sound windows 7 ultimate 64 acer Aspire 7738G

Hi I cant get the sound to work under windows 7 ultimate 64 on my notebook acer Aspire 7738G and I have tryed the driver from the support site but i wont wok or just did somsing wrong

Is this the drivers you downloaded:

Yea that the driver but I will try it aging and set the playback thing

I just says Therer is no sound device installed when i click to see the sound deviceses so what to do dosent think i got the right driver

I dount think it reorginice then drivers beacuse I download the realtek 240 driver and it dident work

I cane fine install the driver but the I wont work the i tryes to uninstall the drive and the it says " realtek hd driver remove failuer" so what to do

I just pressed F8 at start up clicked on the "disable driver signature enforcement"

Now I have to press disable driver signature enforcement at strtup every time when I want to have sound so I think that therer is a problem with the windows 7 so whats the problem

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