Avast shields are off

I have been trying the Sandbox feature in Internet Security 8, and chose a number of Folders to run in the Sandbox which included Avast, but everytime i reboot the Shields are All off and when i try to turn them on it says:

C:/ProgramFiles/Avast/VisthAux.exe The Extended attributes are inconsistent.

I have tried Repair and a Complete Reinstallment but get the same error.

One of My Browsers (Internet Explorer) has stopped working, Firefox is still working but have had a number of problems since trying out the Sandbox options.