When using Windows Vista/Seven with the ASUS Eee PC the ACPI Drivers from the ASUS page will fail with the messages "Missing Audio Driver, audio hot key is void" and "Missing VGA Driver, Display switch hot key is void". And the function keys won't work correctly. There's a simple way to resolve the issue:

If you got problems or questions please take a look at this thread.

Installation:
  • 1. Uninstall your current ACPI Driver
  • 2. Download and extract Asus_ACPI_Driver.zip
  • 3. Execute Asus ACPI Driver.msi and follow the instructions
  • 4. Restart Windows


Against the Intel igfxext.exe not running. Disable Display Switch hot key. error message with Windows 7 do the following:

  • 1. Uninstall your current display driver and restart windows
  • 2. Download the working version of the driver
  • 3. Install the driver with administrator rights in the Windows Vista compatibility mode
  • 4. Restart Windows


Note: The ACPI Fix I wrote is not needed anymore as ASUS has released drivers for Windows Vista/Seven in the meanwhile.