avast! Setup Fatal Error broke Windows Installer

[Flowbow]

Hello,

I cant Install EAs Origin Software or Valve Steam , because I recieve following Error Message:

avast! Setup Fatal Error : Error reading product data from "C:\part-setup_ais-ffffffff.vpx". Setup cannot continue.

This message popped up since upgrade from Avast 7 free to Avast 8 free , but until now it never impeded any installations. I searched the forums regarding this error and uninstalled Avast in Safemode and ran the aswclear.exe with any possible version a couple of times. I used CCleaner and manually searched my registry for every entry concerning Avast, but this error doesn't go away.

The strange thing is that Avast 8 runs fine and updates without problem, but I need to install other software too. Help would be greatly appreciated, because I dont want to reinstall my Windows again.

System Specs: AMD X4 945, 6 GB RAM, AMD Radeon HD 7850, Windows 7 SP1 64Bit

[Flowbow]

Ok I solved it,

There was an invisible file named "program" in my Root directory. Windows treated it like a system protected file and I had to enable the visibility in my Explorer options.

I deleted it in Admin mode and now the other software seems to install correctly.

Problem solved and this thread can be closed.