I've emptied VDD
You must have the following entry there:
C:\Program Files\Alwil Software\Avast4\aswMonVd.dll
Check all these keys (if you have them all):
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\VirtualDeviceDrivers\\VDD
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\VirtualDeviceDrivers\\VDD
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet002\Control\VirtualDeviceDrivers\\VDD
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet003\Control\VirtualDeviceDrivers\\VDD
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet004\Control\VirtualDeviceDrivers\\VDD