Even though there are Windows Vista and Windows 7 and other OS in the market, there are still a lot of people who use Windows XP as their operating system. If you are also one of the people who use Windows XP, you must be familiar with this issue—audio driver installation fails to complete and thus leading to no-sound system. To fix it, many agree that normal ways can’t work in most cases. Therefore in this post, I will introduce you why the problem exists and some ways to get it fixed. Two kinds of audio drivers In order to know the reason why this happens, we first need to know the audio driver. There are two kinds of audio drivers: Bus driver and function driver. The bus driver realizes the basic audio functions and normally it’s integrated in the operating system ( It’s called UAA in Windows XP while in Windows Vista and 7, this issue doesn’t exist since they will use quite different solutions). The function driver mainly realizes the special or strengthened functions of audio device ( audio card). The chipset manufacture provides the function drivers and normally we will call them audio driver (The first thing we manually install after system installation). Reason why audio driver fails installation in Windows XP In windows XP, the system provides HD audio Bus driver and will automatically detect your audio device during system install. When it finds there is audio device in the computer, it will automatically install the Bus Driver immediately. Here comes the reason why audio driver fails install in windows XP. Though what the chipset manufacture provides is function drivers, usually they still come with their own Bus driver. So when installing audio driver in Windows XP, the installation could be unsuccessful due to the compatibility or conflicts issue of the two Bus drivers. How to get audio driver installed under Windows XP Even though we have the reason for the issue, it’s still not easy to fix since we can’t prevent the Windows XP from installing Bus driver automatically and neither can we know whether the audio driver download comes with the Bus driver. Therefore, what we can do is either trying several times and see whether we are lucky enough to find a compatible driver without Bus driver coming along or uninstalling the Bus driver that automatically installed by the Windows. But practically we will soon find that it’s impossible to uninstall the Bus driver since it’s working the moment you turn on the computer. So now, the only way seems to uninstall it under safe mode as in safe mode only necessary drivers are started and audio drivers are not necessary kind. Uninstall the Bus driver under safe mode Start the safe mode, enter the system and C: \WINDOWS\System32\drivers catalogue. Delete all the files that begins with Had ( ignore capital or lower cases) such as hdaudbus.sys, HdAudio.sys etc. After that, enter the device manager and change “Microsoft UAA Bus Driver for High Definition Audio” settings to disabled and delete it. If there is “no hardware found” notice or you want to install it yourself, you can download driver for the audio card and then install it. More Until now, if your problem still exists, it could be due to the fact that you didn’t operate rightly. This time, you can operate again. If no work again, the problem could be caused by other reasons. In this case, you need to find other ways.