error when installing avast

I recently had to restore my computer from a previous windows setting and when I did my avast started saying it was not on. I tried to remove the program so I could reinstall it but it failed to uninstall saying a file is missing. I’ve tried to reinstall the program but it keeps popping up with two error messages during set up.

c:\Program Files\AVAST Software\Avast\setup\part-setup_ais-7e2,vpx".Setup

C:\Program Files\AVAST Software\Avast\setup.ove’executable. (code 0x5)

Can anyone tell me what is wrong with my avast and what I can do to fix it please? Thank you.

System restore often corrupts avast install unless you turn off selfprotect module first

So you need to reinstall… see www.avast.com > support > downloads > uninstall utility