Understanding UAA errors
You are probably looking for info on UAA drivers because you have changed the operating system on your notebook PC, and the sound no longer works. UAA is a Microsoft driver and you should search their site for additional information. This document will explain what UAA is, how it can be affected by operating system changes, and describe in general terms how to repair problems with UAA.
Microsoft's Universal Audio Architecture (UAA) is a type of audio driver supported by the operating system. Many HP and Compaq PCs have an Intel High Definition Audio which uses UAA and Realtek ALC. All of these audio components work together to provide a high-definition audio experience on your notebook PC.
When the operating system on a computer is changed, the drivers that worked for one operating system may not work with the new operating system, and may cause error messages to appear, or cause the audio not to function at all. Additionally, if newer UAA files have been replaced with older versions, you may need to reinstall a newer sound driver package.
Resolving UAA errors
HP cannot currently deliver UAA as a separate download, only the audio driver files for audio hardware. UAA can only be restored through the HP Recovery Process. For more information, please refer to the See also section.
In the event you have upgraded/downgraded Windows, you can download full audio driver packages directly from Realtek.
I am trying to install an audio driver and a window opens stating I need a UAA Bus driver. Why?
Before the audio driver can be installed, the installer first needs to verify that the correct UAA files are installed and are intact. If the installer cannot detect the proper files for UAA, the installer opens the message window and exits the installation. The installation does this to protect your PC from further problems that could occur if the UAA files were missing or the wrong files were used.
These messages are most likely to occur if you have changed the operating system (for example, from Windows Vista or Windows 7 to Windows XP). These messages can also occur if the login account does not have the proper permissions to install the software. Obtain and install a new audio driver package that matches the new operating system. For XP, you may need to install an Updated UAA driver package it, before you install an XP audio driver: Microsoft QFE Update (KB835221) to Support UAA Bus Driver (hosted by HP in English).
HP Notebook PCs - Using HP Backup and Recovery Manager (Windows Vista)
Realtek support site (in English)
Microsoft: Audio Device Technologies for Windows (in English).